Category: ICSE

Solving ICSE Class 10 English Language Previous Year Question Papers ICSE Class 10 English Language Question Paper 2022 Semester 2 is the best way to boost your preparation for the board exams.

ICSE Class 10 English Language Question Paper 2022 Solved Semester 2

Maximum Marks: 40
Time Allowed : One and a half hours

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 10 minutes.
• This time is to be spent in reading the question paper.
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions.
• The marks intended for questions are given in brackets [ ].

Question 1.
Write a composition (300 – 350 words) on any one of the following:   [20]
(i) If you were granted a special wi sh what would you choose? Say why you would make this choice and how it will be useful to you and your loved ones.
(ii) Write a short story in which the main characters are an old woman, a small child and a little puppy.
(iii) “More learning happens outside the classroom than inside it.”
Express your views either for or against this statement.
(iv) Describe a time when all the lights in your locality went off. What were the sounds you heard as you sat in the darkness ? How did you feel when the lights came on ?
(v) Study the given picture. Write a short story or description or an account of what the picture suggests to you. Your composition may be about the subject of the picture or you may take suggestions from it.

Answers:
(i) Wish to be a Millionaire
If I were granted a special wish, I would choose to become a millionaire. It does not mean that I am money-minded. I know that money matters a lot to me and my family. Moreover, with a lot of money I would be able to do some urgently needed social work. So my wish to be a millionaire is not merely for my personal well-being but for the well-being of others.

First of all, I would set aside a part of the money to be spent on my education. I want to become a surgeon for which I would need a lot of money. I would be able to fully concentrate on my ambition without any care for the money-aspect involved in achieving it. Then a part of money I would invest in buying shares of promising companies – IT, pharmaceutical firms, etc.  which might give me ample dividends in future.

Then to help my dear parents I would buy them a good house w ith all modem amenities. The house might not be big, but it would be in a good locality. I would not spend much money on useless, luxurious items. As we have already a car, I don’t think we need to go in for another. In order to help my elder brother. I would give him some money to invest in his business. I think he would be happy and satisfied.

We belong to a remote village where there is no dispensary. The villagers have to come to the city even for minor medical problem. I would donate money to the Panchayat of the village to set up a dispensary there and arrange for the services of medical staff needed. This dispensary, I hope, would prove to be highly beneficial to the villagers. May God help me fulfil this wish of mine!

(ii) Duffy – A Dear Puppy !
The old woman was a rag-picker. She lived in a small hut on the outskirts of the city. Her hut was located some distant away from other huts of folks of her own profession, if you call it a profession. She had a seven years old son who would accompany her in his rags to far-off places and help her pick up broken plastic bottles, cups, screws, and such paraphamalia. The morning session from 5 to 7 was the most busy for them.

One day the mother-son duo found that a small puppy followed them wherever they went. The puppy did not move away even when the woman tried to shoo it away. It came right to the doorstep of their hut, and then settled itself luxurously in one comer.

Days passed, the puppy was now a member of the woman’s household. It was bring fed on pieces of stale bread or a stray biscuit, if there was any. It seemed to like the boy the most.

“Roomi, give this bread to puppy,” Mother said. The boy thought they should now name the puppy. So the puppy came to be called ‘Duffy’- a name the boy had heard a rich man use for his pet-dog.

Duffy soon grew up more on the crumbs of affection and care than on the crumbs of dry bread. He took upon himself the duty to guard the house. He would bark to keep off strangers. Roomi would like to spend his spare time in playing with Duffy. Duffy soon learnt to catch the ball thrown in the air. He also learnt to obey simple commands of Roomi. Mother would remain busy with her own routine.

It was a very hot summer night. Duffy was lying near the gate. Roomi and his mother were sleeping on the bare floor of the small open space before their room. Suddenly Duffy saw something black crawling outside the gate, trying to enter the hut. Instinctively, he pounced upon the intruder and began to bit it hard.

The sun rose as usual. Roomi and his mother woke up to go on their usual round of rag-picking. Roomi was surprised to find Duffy nowhere. He opened the gate. His Duffy was lying dead, and beside it lay a big cobra, dead with a number of wounds on its body.

Duffy was no more. Roomi missed him a lot. He would often weep in the memory of his dear friend ! Mother would console him with useless words.

(iii) “More learning happens outside the classroom than inside it.”

It is perfectly true that more learning happens outside the classroom than inside it. Classroom learning is no doubt valuable. It teaches us a lot. But the world outside the classroom is a great teacher. The things we learn at home and from our interactions with our friends, relatives and even strangers are of greater value and make us wiser to cope up with the demands and challenges of life.

For example, there are many life skills that we learn outside the classroom. It is from our parents that we learn how to sit, stand, walk and talk properly. If we are alert we learn from others all those socio-cultural values that are essential for us to learn and imbibe. When we go to a shop to buy anything, we learn many things-how to select or reject something, how to make a fair bargain, how not to be trapped by gullible talks of the shopkeeper, or by attractive labels.

When we go to an office, we learn how to express our views in a clear, concise manner. When we attend a camp or seminar, there is much food for thought. We learn the values of keeping our environment clean and safe, of saving water, of helping the needy and of facing natural disasters, etc.

It is from the outside world that we learn problem solving and decision-making. In fact, when we are in a difficult situation that we learn how to come out of it successfully. We have to have out-of-the box ideas to deal with an unusual situation or challenge. We learn from the experiences of our peers who faced such situations in the past. We formulate our own strategy. These are all problem-solving techniques which are learnt out of the classroom. If we are good problem-solvers we are also good decision makers.

Thus, we should never shut our eyes and ears to the outside world of our homes or classrooms. There is much that we can learn from others in the wide world.

(iv) Sounds in the Dark
I live in Preet Nagar, a developing colony, out-side the city. Only a few houses have come up. So the area is mostly deserted, especially during nights. Only a few dare-devils come to, or go out of, our colony after 10 p.m. There are frequent power cuts here.

One monsoon night I was all alone lying on my cot on the roof of my house. A few street lights were on. Suddenly the lights went off. There was pitch darkness all around. The sky was overcast. So there was no moonlight or starlight, whatsoever. I decided to keep lying.

What else I could do? A number of sounds assailed me as I tried to close my eyes and go to sleep. There were crackling, snapping and whining noises. Sometimes I thought these sounds were coming from the cluster of trees standing towards the left’ of our house. Sometimes I thought these are the sounds coming from electric wires round our roof.

A little later I heard multitude of natural sounds from various insects and birds sitting in trees. There was buzzing, chirping, shrieking, flapping, flittering, and what not. Birds and insects do not seem to rest at night. They continue doing one thing or the other.

I was then startled by a roar of thunder in the sky. There was a flash of lightning. Dark clouds could be seen moving menacingly. I thought it would start raining, but it didn’t. So I did not try to go down.

I was really frightened when I heard sounds of soft footsteps on my staircase. I thought of a thief or a robber at once. I was relieved when I found a cat passing by my bed carelessly.

Thank God, the lights came after an hour or so. I felt relieved and had a round on my roof. There was nothing to be afraid of. I lay on my bed and soon sleep overpowered me. When I woke up, I remembered the experience of sounds in the dark and shuddered.

(v) The picture shows an adolescent choosing some tool to set right the car beside him. He must be fourteen or sixteen. He is in a dirty vest and perhaps in a half-pant. Let us name him Mukesh.

Mukesh belongs to a very poor family. He has not been sent to school by his parents. His stem father has always looked upon education as useless, perhaps because he has himself been deprived of it. Moreover, he wants all male members of family to start earning as soon as possible. So Mukesh has never seen the face of a school. When he was five or six, he was sent to a ‘dhaba’ owner. He worked there for five long years. He learnt a lot many things these washing dishes, cleaning and sweeping, making tea and preparing some dishes. He also learnt playing various card games, and abuses from special nocturnal customers like truck drivers.

On his way home he would pass by car-repair shops. He would often stand and stare at beautiful cars, big or small.

He got fascinated by the sights and sounds of cars. The idea of becoming a motor mechanic slowly but steadily seized him. One day he met the owner of a garage and expressed his wish. The owner, a Sardaiji, looked at him contemptuously and shooed him away. But he was determined. He continued to pester Sardaiji. One day Sardaiji was in a good mood. In fact, he needed a helper. So he asked him to report the next day.

Mukesh came to the garage an hour earlier. He was given odd, useless jobs at first. But Mukesh proved to be a good learner. He became a full- fledged mechanic in a year or so.

Now he is happy and satisfied. He is given a regular pay. He hopes one day he will open his own garage.

Question 2.
Select any one of the following :  [10]
(i) Your favourite aunt/uncle has asked you what you would like as a gift for your birthday. What gift would you choose (specify) and why would you choose this ? Write a letter to your aunt/uncle thanking her/him for the kind thought and telling her/him about the gift of your choice.
(ii) You are being considered for a Head boy/Head girl position in the school.’Write a letter to the Principal explaining why you think you would make a good Head boy/Head girl. Why does the role interest you? Describe ways in which you would carry out your responsibilities.
Answers:
(i) 125BRamNiwas
Inderlok Colony
Lucknow – 226002
May 5, 20…
Dear Uncle
Received your letter today and was really excited, to go through the contents. Thanks a lot for the kind offer you have given me to choose the birthday present I would like to have.

Dear uncle, I would like to have a smart phone as my birthday present. Most of my friends have smart phones. They have internet connections also. Their phones are very helpful to them in their studies also . When I am in their company and they are using their smart phones I feel a bit inferior to them because my simple phone does not have all those facilities which their phones have. I am sure this gift will be veiy helpful to me in my studies as well as in my interaction with my dear friends.

Thank you once again for asking nje about my choice. Pay my regards to dear aunt.

Your loving nephew
Somesh

(ii) Subash Hostel
Shimla
23 April 20…

The Principal

I have learnt from a very reliable source that my name is being considered for the position of the Head Boy in the school. I feel, that if I am made the Head Boy I shall discharge my duties in a very responsible manner.

The Head Boy, I feel, is a sort of bridge between the students and the administration. It is his duty to convey to the administration the problems and difficulties being faced by the students. He is also expected to help the principal in maintaining perfect discipline in the school. Sir, the role of the Head Boy suits me perfectly well as I have always aspired to be of some help to the administration in bringing about peace and order in the school so that academic pursuits go on undisturbed. I assure you, if your choice falls on me I shall not disappoint you. I shall carry on my responsibilities nicely.

Yours obediently
Kamal Kishore

Question 3.
(i) March 22^nd is World Water Day. The school Dramatics Club is planning to stage a one-act play to mark the occasion and create awareness. Write a notice to be put up on the school notice board, giving details of the event. [5]
(iii) Write an e-mail to the Principal of a neighbouring school requesting him/her to send a team of children to participate in the interactive session which will follow the play. [5]
Answers:
(i) AB PUBLIC SCHOOL, NOIDA NOTICE

March 15, 20…

Observance of World Water Day
This is to inform you that Kalidasa Dramatics Club is planning to stage a one-act play to mark the World Water Day in the school auditorium on 22nd of March, 20.. at 10 a.m. The purpose is to create awareness among the people not to waste water. R.K. Bansal, the famous environmentalist will deliver a talk. All are requested to attend.

Ram Parkash
Secretary

(ii) From : ramparkashl25@ gmail. com
Date: 15:03:2022 04:15:25

To : [email protected]
Subject: Request to send team of children.

Sir
The Kalidasa Dramatics Club of our School is going to celebrate the World Water Day on 22nd March. The club is going to stage a one- act play to create awareness among the people not to waste water as it is a precious thing. Sh. R.K. Bansal, the famous environmentalist has been invited to deliver a talk. The talk will be followed by an interactive session. It will be very nice if you send a team of children to attend the talk and particpate in the interactive session after the play. Looking forward to a favourable response.

Ram Parkash
Secretary

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2015 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2015 Solved

Time: 1 1/2 hour
Maximum Marks: 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section I (40 Marks)
Attempt all questions from this Section

Question 1
(a) Name the following:
(i) The process of uptake of mineral ions against the concentration gradient using energy from cell.
(ii) The form in which glucose is stored in liver.
(iii) The vein that carries oxygenated blood.
(iv) The cross between two parents having one pair of contrasting characters.
(v) The structure formed by the villi of the embryo and the uterus of the mother. [5]
Answer:
(i) Active transport
(ii) Glycogen
(iii) Pulmonary vein
(iv) Monohybrid cross
(v) Placenta

(b) The statements given below are False. Rewrite the correct form of the statement by changing the word which is underlined:
(i) Alpha cells of pancreas secrete Insulin.
(ii) Formalin is an example of an Antiseptic.
(iii) CNG is mainly responsible for the formation of acid rain.
(iv) Sulphadiazine is an example of an Antiseptic.
(v) Cretinism is caused due to deficiency of Adrenaline. [5]
Answer:
(i) Alpha cells of pancreas secrete glucagon.
(ii) Formalin is an example of a disinfectant.
(iii) Sulphur dioxide is mainly responsible for the formation of acid rain.
(iv) Sulphadiazine is an example of a sulpha drug.
(v) Cretinism is caused due to deficiency of thyroxine.

(c) Choose the correct answer from the four options given below:
(i) A single highly coiled tube where sperms are stored, gets concentrated and mature is known as:
A. Epididymis
B. Vas efferentia
C. Vas deferens
D. Seminiferous tubule
Answer:
(i) A. Epididymis

(ii) Chromosomes get aligned at the centre of the cell during:
A. Metaphase
B. Anaphase
C. Prophase
D. Telophase
Answer:
A. Metaphase

(iii) BCG vaccine is effective against
A. Cholera
B. Mumps
C. Tuberculosis
D. Measles
Answer:
C. Tuberculosis

(iv) Which one of the following is associated with the maintenance of the posture?
A. Cerebrum
B. Cerebellum
C. Thalamus
D. Pons
Answer:
B. Cerebellum

(v) An example of non-biodegradable waste is
A. Vegetable peels
B. Sewage
C. Livestock waste
D. DDT [5]
Answer:
D. DDT

(d) Mention the exact location of the following structures:
(i) Thylakoids
(ii) Organ of Corti
(iii) Lenticels
(iv) Bicuspid valve
(v) LoopofHenle [5]
Answer:
(i) Thylakoids: Present in colourless ground substance/Stroma/Matrix of chloroplast
(ii) Organ of Corti: In the Cochlea / On the basilar membrane of median canal in Cochlea
(iii) Lenticels: Present on the older stems of plants in place of stomata.
(iv) Bicuspid valve: Located at the aperture between the left auricle and the left ventricle of the heart.
(v) Loop of Henle: Runs in the medulla of the kidneys and connects the proximal convoluted tubule and the distal convoluted tubule.

(e) The diagram given below represents a certain stage of mitosis:

(i) Identify the stage of cell division.
(ii) Name the parts labelled A and B
(iii) What is the unique feature observed in this stage?
(iv) How many daughter cells are formed from this type of cell division? [5]
Answer:
(i) Anaphase
(ii) A – Spindle fibre B – Centromere
(iii) Chromosomes are seen moving towards the poles.
(iv) This type of cell division (mitosis) results in the formation of two daughter cells.

(f) Given below is an example of a certain structure and its special functional activity. On a similar pattern fill in the blanks with suitable functions:
Example: Chloroplast and photosynthesis
(i) Xylemand _____
Answer:
Xylem and Absorption and conduction of water.

(ii) Ciliary body and _____.
Answer:
Ciliary body and Alteration of the shape of the eye lens.

(iii) Seminiferous Tubule and ____.
Answer:
Seminiferous tubule and Spermatogenesis.

(iv) Thyroid gland and ____.
Answer:
Thyroid gland and Secretion of thyroxine and calcitonin.

(v) Eustachian Tube and ____. [5]
Answer:
Eustachian tube and Equalising air pressure.

(g) Rewrite and complete the following sentences by inserting the correct word in the space indicated:
(i) The phenomenon of loss of water through a cut stem or injured part of plant is called _____.
Answer:
The phenomenon of loss of water through a cut stem or injured part of plant is called bleeding

(ii) ____ is the scientific name of garden pea, which Mendel used for his experiments.
Answer:
Pisum sativum is the scientific name of garden pea, which Mendel used for his experiments.

(iii) A fluid that occupies the larger cavity of the eye ball behind the lens is _____
Answer:
A fluid that occupies the larger cavity of the eye ball behind the lens is vitreous humour.

(iv) Oxygen combines with haemoglobin present in RBC and forms _____
Answer:
Oxygen combines with haemoglobin present in RBC and forms oxyhaemoglobin.

(v) ____ causes corrosion of the marble or brick surface.
Answer:
Acid rain causes corrosion of the marble or brick surface.

(h) Match the items in Column ‘A’ with those which are most appropriate in Column ‘B’ Rewrite the matching pairs as shown in the example: [5]
Example: Fibrinogen – Clotting of blood.

Answer :
(1) Allele – Alternate forms of genes
(2) Leydig cells – Testosterone
(3) Utriculus – Static equilibrium
(4) Snake bite – Tourniquet
(5) Euro IV norms – Control of automobile exhaust

Section II (40 Marks)
Attempt any four questions from this Section

Question 2.
(a) The diagram below shows two test-tubes A and B. Test-tube A contains a green water plant. Test- tube B contains both a green water plant and a snail. Both testtubes are kept in sunlight. Answer the questions that follow:

(i) Name the physiological process that releases the bubbles of oxygen.
(ii) Explain the physiological process as mentioned above in Q.2 (a)(i).
(iii) What is the purpose of keeping a snail in test-tube ‘B’?
(iv) Why does test-tube ‘B’ have more bubbles of oxygen?
(v) Given an example of a water plant that can be used in the above process.
(vi) Write the overall chemical equation for the above process.
Answer:
(i) Photosynthesis releases the bubbles of oxygen.
(ii) Photosynthesis is a physiological process by which plant cells containing chlorophyll produce food in the form of carbohydrates by using carbon dioxide, water and light energy. Oxygen is released as a by-product.
(iii) Carbon dioxide released by the snail during respiration is used by the plant for photosynthesis. This increases the rate of photosynthesis in the plant placed in test tube B. This also suggests that both respiration and photosynthesis are complementary processes to maintain the concentration of oxygen and carbon dioxide in the atmosphere.
(iv) In test tube B, a plant and a snail are kept. The plant in test tube B has more concentration of CO₂ available because the snail releases CO₂ during respiration. This increases the rate of photosynthesis in the plant placed in test tube B which leads to the release of more amount of oxygen.
(v) Hydrilla
(vi) Chemical equation for photosynthesis:

(b) Give the biological/technical terms for the following:
(i) A mixture, of smoke and fog.
(ii) Capacity of our body to resist diseases.
(iii) Fixing of developing zygote on the uterine wall.
(iv) The permanent stoppage of menstruation at about the age of 45 years in a female.
(v) The hormone increasing reabsorption of water by kidney tubules.
(vi) A thin membrane covering the entire front part of the eye.
(vii) The lens of eye losing flexibility resulting in a kind of long-sightedness in middle aged people.
(viii) The number of persons living per square kilometre at any given time.
(ix) The sound produced when the atrio-ventricular valves close in the heart.
(x) The process by which white blood cells engulf bacteria. [5]
Answer:
(i) A mixture of smoke and fog – Smog
(ii) Capacity of our body to resist disease – Immunity
(iii) Fixing of developing zygote on the uterine wall – Implantation
(iv) The permanent stoppage of menstruation at about the age of 45 years in a female – Menopause
(v) The hormone increasing reabsorption of water by kidney tubules – Anti-diuretic hormone (Vasopressin)
(vi) A thin membrane covering the entire front part of the eye – Conjunctiva
(vii) The lens of eye losing flexibility resulting in kind of long-sightedness in middle aged people – Presbyopia
(viii) The number of persons living per square kilometre at any given time – Population density
(ix) The sound produced when atrioventricular valves close in the heart – Lubb sound
(x) The process by which white blood cells engulf bacteria – Phagocytosis

Question 3
(a) An apparatus as shown below was set up to investigate a physiological process in plants. The setup was kept in sunlight for two hours. Droplets of water were then seen inside the bell jar. Answer the questions that follow:

(i) Name the process being studied.
(ii) Explain the process named above in Q.3(a)(i).
(iii) Why was the pot covered with a plastic sheet?
(iv) Suggest a suitable control for this experiment.
(v) Mention two ways in which this process is beneficial to plants.
(vi) List three adaptations in plants to reduce the above mentioned process. [5]
Answer:
(i) Transpiration
(ii) Transpiration is a process during which water is lost in the form of water vapour through the aerial parts of the plant. All plants are continously absorb water through their roots. More than 90% of this water is lost to the atmosphere as water vapour during transpiration.
(iii) The pot is covered with a plastic sheet to prevent the evaporation of water from the soil.
(iv) A control for this experiment will be an empty polythene bag with its mouth tied.
(v) Transpiration is beneficial to plants in the following ways:

• It creates a suction force in the stem which enables the roots to absorb water and minerals.
• It helps in cooling the plant in hot weather.

(vi) Adaptations in plants to reduce transpiration are

• Leaves may be modified into spines as in cactus or into needles as in pines.
• The number of stomata is reduced and they may be sunken in pits.
• Leaves may be folded or rolled up.

(b) Briefly answer the following questions:
(i) State two reasons for the increase of population in India.
(ii) What is the significance of amniotic fluid?
(iii) What is the function of ear ossicles?
(iv) Mention any two activities of the WHO.
(v) State Mendel’s law of Dominance. [5]
Answer :
(i) Reasons for the increase of population in India:

• Most Indian families desire to have at least one son. Hence, a couple produces several children till a son is born.
• Most of the rural population is still illiterate, ignorant and superstitious.
  Therefore, they do not make any effort to avoid pregnancy.

(ii) Significance of amniotic fluid:

• It protects the embryo from physical damage by jerks and mechanical shocks.
• It also maintains even pressure all around the embryo.

(iii) Function of ear ossicles:

• Ear ossicles once set in vibrations transmit the vibration to the oval window which sets the cochlear fluid into vibration.

(iv) Activities of WHO:

• Collecting and supplying information about the occurrence of diseases of an epidemic nature.
• Supplying information on the latest developments about the use of vaccines, cancer research, nutritional discoveries, control of drug addiction and the health hazards of nuclear radiation.
• To promote and support projects for research on diseases.
• To organic compaigns for the control of epedemic and endemic diseases.

(v) Mendel’s law of dominance:
Out of a pair of contrasting characters present together, only one is able to express itself, while the other remains suppressed.

Question 4
(a) The diagrams given below are cross sections of blood vessels:

(i) Identify the blood vessels A, B and C.
(ii) Name the parts labelled 1 to 3.
(iii) Name the type of blood that flows through A.
(iv) Mention one structural difference between A and B.
(v) In which of the above vessels does exchange of gases actually take place? [5]
Answer:
(i) A – Artery
B – Vein
C – Blood capillary
(ii) 1 – External layer of connective tissue / Tunica externa
2 – Lumen
3 – Muscular tissue
(iii) Oxygenated blood flow through A
(iv) Structure difference between A (artery) and B (vein):
A (Artery): Valves are not present / Thick muscular layer / Narrow lumen.
B (Vein): Valves are present / Thin muscular layer / Wide lumen.
(v) In blood capillaries, the exchange of gases takes place.

(b) Differentiate between the following pairs on the basis of what is mentioned within brackets:
(i) Diffusion and Osmosis (Definition)
(ii) RBC and WBC (Shape)
(iii) Tubectomy and Vasectomy (Part cut and tied)
(iv) Vasopressin and Insulin (Deficiency disorder)
(v) Rods and Cones of Retina (Type of pigment) [5]
Answer :
(i) Diffusion and Osmosis (Definition):
Diffusion
Diffusion is the free movement of molecules of a substance from the region of its higher concentration to the region of its lower concentration when the two substances are in direct contact.
Osmosis
Osmosis is the diffusion of water molecules across a semi-permeable membrane from a more dilute solution (with a lower solute concentration) to a less dilute solution (with a higher solute concentration).

(ii) RBC and WBC (Shape):
RBC : RBCs are disc-like, flat at the centre and round at the periphery.
WBC : WBCs are amoeboid or irregular in shape.

(iii) Tubectomy and Vasectomy (Part cut and tied):
Tubectomy : Fallopian tubes or oviducts are cut and ligated and then tied with nylon threads to close the passage of the egg.
Vasectomy : Vas deferentia each from testis are cut and ligated then both the cut sides are tied with nylon threads.

(iv) Vasopressin and Insulin (Deficiency disorder):
Vasopressin : Insufficient secretion of vasopressin causes diabetes insipidus.
Insulin : Insufficient secretion of insulin causes diabetes mellitus.

(v) Rods and Cones of Retina (Type of pigment):
Rods : Rods produce rhodopsin.
Cones : Cones produce iodopsin.

Question 5
(a) The diagram given below shows a section of human kidney. Study the diagram carefully and answer the questions that follow:

(i) Label the parts numbered 1 to 4.
(ii) Why does part ‘2’ have a striped appearance?
(iii) What is the fluid that passes down part ‘4’? Name the main nitrogenous waste present in it.
(iv) Mention the structural and functional units of kidneys.
(v) Name the two major steps in the formation of the fluid mentioned in Q.5 (a) (iii). [5]
Answer:
(i) 1 – Cortex
2 – Medulla
3 – Renal pelvis
4 – Ureter
(ii) Due to the presence of Henle’s loops and collecting ducts of nephrons.
(iii) Urine passes down part ‘4’, i.e. ureter. The main nitrogenous substance present in it is urea.
(iv) Nephrons are the structural and functional units of the kidneys.
(v) The two major steps in the formation of urine are ultrafiltration and selective reabsorption,

(b) Draw neat and labelled diagrams of the following:
(i) Malpighian Capsule
(ii) A Myelinated Neuron [5]
Answer :
(i) Malpighian capsule

(ii) A myelinated neuron

Question 6
(a) The diagram given below shows the male urinogenital system of a human being. Study the diagram and answer the questions that follow:

(i) Label the parts numbered 1 to 8.
(ii) Name the corresponding structure of part (4) in female reproductive system.
(iii) What is the role of part 7?
Answer:
(i) 1 – Urinary bladder
2 – Ureter
3 – Prostate gland
4 – Vas deferens
5 – Urethra
6 – Testis
7 – Scrotum
8 – Epididymis

(ii) Fallopian tube or oviduct
(iii) Scrotum is a sac-like structure which encloses the testes. Because it is situated outside the body cavity, it maintains the lower temperature favourable for the production of sperms.

(b) In a homozygous plant round seeds (R) are dominant over wrinkled seeds (r):
(i) Draw a Punnett square to show the gametes and offspring when both the plants have heterozy¬gous round seeds (Rr).
(ii) Mention the Phenotype and Genotype ratios of the offsprings in F2 generation.
(iii) Name the sex chromosomes in human males and females.
(iv) Briefly explain the term ‘Mutation’.
(v) What is the number of chromosomes in the gametes of human beings? [5]
Answer :
(i) P₁ = Rr
P₂ = Rr

(ii) Phenotypic ratio of the offspring in F₂ generation: 3 : 1
Genotypic ratio of the offspring in F₂ generation: 1 : 2 : 1
(iii) Sex chromosomes in human males are X and Y.
Sex chromosomes in human females are XX.
(iv) Mutation is the sudden change in one or more genes, or in the number or in the structure of chromosomes.
(v) The number of chromosomes in the gametes of human beings is 23.

Question 7
(a) The diagram below represents the human heart in one phase of its function. Study the diagram carefully and answer the questions that follow:

(i) Name the phase.
(ii) Which part of the heart is contracting in this phase?
Give a reason to support your answer.
(iii) Name the parts labelled 1 to 4.
(iv) What type of blood flows through ‘2’?
(v) State the function of the part numbered ‘5’.
(vi) Name the membrane that covers the heart. [5]
Answer:
(i) Ventricular Diastole and auricular systole
(ii) Ventricles are contracting in this phase. In the diagram given, tricuspid valves and bicuspid valves are closed, while the semi-lunar valves are open.
(iii) 1 – Pulmonary artery
2 – Aorta
3 – Bicuspid valve
4 – Aortic Semilunar valve (aortic semilunar valve)
5 – Pulmonary semilunar valve
(iv) Oxygenated blood flows through ‘2’, i.e. aorta.
(v) ‘5’ is pulmonary semilunar valve. It prevents the backflow of blood into the right ventricle at the time of ventricular diastole.
(vi) Pericardium covers the heart.

(b) Explain the following terms:
(i) Greenhouse effect
(ii) Turgor pressure
(iii) Selective reabsorption
(iv) Natality
(v) Pulse
Answer :
(i) Greenhouse effect:
Gases such as CO₂, methane, nitric oxide and nitrous oxide in the atmosphere act as greenhouse gases. Their increased concentration in the atmosphere prevents the escape of heat which warms the air. This is called greenhouse effect.
(ii) Turgor pressure:
In a turgid plant cell, the pressure of the cell contents on the cell wall is called the turgor pressure.
(iii) Selective reabsorption:
The glomerular filtrate entering the renal tubule contains many useful substances.
Hence, as the filtrate passes down the tubule, water and other substances required by the body are reabsorbed. This reabsorption occurs only to the extent that the normal concentration of the blood is undisturbed. This entire process is called selective reabsorption.
(iv) Natality : The number of live births per 1000 people of population per year is called natality.
(v) Pulse : The pulse is the alternate expansion and elastic recoil of the wall of the artery during ventricular systole.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2017 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2017 Solved

Time : (One hour and a half)

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section – I (40 Marks)
(Attempt all questions from this section)

Question 1.
(a) Name the following : [5]
(i) The process by which root hairs absorb water from the soil.
(ii) The organ which produces urea.
(iii) The kind of lens required to correct Myopia.
(iv) The pituitary hormone which stimulates contraction of uterus during child birth.
(v) The international health organisation which educates people in accident prevention.
Answer:
(i) Endosmosis
(ii) Liver
(iii) Concave/Diverging lens
(iv) Oxytocin
(v) Red Cross

(b) Choose the correct answer from each of the four options given below : [5]
(i) The prime source of chlorofluorocarbons is
(A) Vehicular emissions
(B) Industrial effluents
(C) Domestic sewage
(D) Refrigeration equipment
Answer:
(D) Refrigeration equipment

(ii) Penicillin obtain from a fungus is
(A) Antibiotic
(B) Antiseptic
(C) Antibody
(D) Antiserum
Answer:
(A) Antibiotic

(iii) Marine fish when placed in tap water bursts because of
(A) Endosmosis
(B) Exosmosis
(C) Diffusion
(D) Plasmolysis
Answer:
(A) Endosmosis

(iv) Surgical method of sterilization in a woman involves cutting and tying of
(A) Ureter
(B) Uterus
(C) Urethra
(D) Oviduct
Answer:
(D) Oviduct

(v) Synthesis phase in the cell cycle is called so, because of the synthesis of more :
(A) RNA
(B) RNA and proteins
(C) DNA
(D) Glucose
Answer:
(C) DNA

(c) The statements given below are incorrect. Rewrite the correct statement by changing the underlined words of the statements.

(i) The Graafian follicle, after ovulation turns into a hormone producing tissue called Corpus callosum.
(ii) Deafness is caused due to the rupturing of the Pinna.
(iii) Gyri and Sulci are the folds of Cerebellum.
(iv) Free movement of solutes in and out of the cell takes place across the cell membrane.
(v) The solvent used to dissolve the chlorophyll pigments while testing a leaf for starch is Soda lime.
Answer:
(i) The Graafian follicle, after ovulation turns into a hormone producing tissue called Corpus luteum.
(ii) Deafness is caused due to the rupturing of the Tyumpanum/Ear drum.
(iii) Gyri and Sulci are the folds of Cerebrum.
(iv) Free movement of solutes in and out of the cell takes place across the cellwall.
(v) The solvent used to dissolve the chlorophyll pigments while testing a leaf for starch is methylated spirit.

(d) Given below are sets of five terms each. Rewrite the terms in correct order in a logical sequence.

Example : Large intestine, Stomach, Mouth, Small intestine, Oesophagus.
Answer : Mouth → Oesophagus → Stomach → Small intestine → Large intestine.
(i) Fibrin, Platelets, Thromboplastin, Fibrinogen, Thrombin.
(ii) Cochlea, Malleus, Pinna, Stapes, Incus.
(iii) Receptor, Spinal cord, Effector, Motor neuron, Sensory neuron.
(iv) Uterus, Parturition, Fertilisation, Gestation, Implantation.
(v) Caterpillar, Snake, Owl, Frog, Green leaves.
Answer:
(i) Platelets → Thromboplastin → Thrombin → Fibrinogen → Fibrin.
(ii) Pinna → Malleus → Incus → Stapes → Cochlea.
(iii) Receptor → Sensory neuron → Spinal cord → Motor neuron → Effector.
(iv) Fertilisation → Uterus → Implantation → Gestation → Parturition.
(v) Green leaves → Catterpillar → Frog → Snake → Owl.

(e) Choose the ODD one out of the following terms given and name the CATEGORY to which the others belong: (5)
(i) Aqueous humour, Vitreous humour, Iris, Central canal
(ii) Formalin, Iodine, DDT, Lime
(iii) ACTH, TSH, ADH, FSH
(iv) Phosphate, RNA, Sugar, Nitrogenous base
(v) Bile, Urea, Uric acid, Ammonia
Answer:

Odd term	Category
(i)    Central canal (ii)    Iodine (iii)    ADH (iv)    RNA (v)    Bile	Parts of eye Disinfectants Harmones of anterior lobe of pituitary. Components of nucleotide. Nitrogenous waste excreted with urine.

(f) Given below are groups of terms. In each group the first pair indicates the relationship between the two terms. Rewrite and complete the second pair on a similar basis. [5]

Example : Oxygen: Inspiration:: Carbon dioxide : Expiration.
(i) Eye Optic nerve : Ear : ……………….
(ii) Cytoplasm : Cytokinesis :: Nucleus : ……………….
(iii) TT : Homozygous : Tt : ……………….
(iv) Foetus : Amnion : : Heart: ……………….
(v) Adenine : Thymine :: Cytosine : ……………….
Answer:
(i) Auditory curve.
(ii) Karyokinesis.
(iii) Heterozygous
(iv) Pericardium
(v) Guanine

(g) Match the items given in Column A with the most appropriate ones in Column B and rewrite the correct matching pairs.

Column A	Column B
1.   Sacculus 2.    Birthrate 3.    DNA and histones 4.    Euro norms 5.    Diabetes mellitus	—   dynamic body balance —   Hyperglycemia —   Hypoglycemia —  Natality —   static body balance —   vehicular standards —   nucleosome

Answer:

Column A	Column B
1.   Sacculus 2.    Birthrate 3.    DNA and histones 4.    Euro norms 5.    Diabetes mellitus	—Static body balance —Natality —   Nucleosome —  Vehicular standards —  Hyperglycemia

(h) The diagram given below represents the location and structure of an endocrine gland. Study the same and answer the questions that follow :

(i) Name the endocrine gland shown in the diagram.
(ii) Name the secretion of the gland which regulates basal metabolism.
(iii) Name the mineral element required for the synthesis of the above mentioned hormone.
(iv) Name the disease caused due to under secretion of the above mentioned hormone in children.
(v) Name the disease caused due to hypersecretion of the above mentioned hormone.
Answer:
(i) The endocrine gland shown is the thyroid gland.
(ii) The secretion of the gland which regulates basal metabolism is thyroxine.
(iii) The mineral element required is iodine.
(iv) The disease caused due to under secretion of the hormone in children is cretinism.
(v) The disease caused due to hypersecretion of the above mentioned hormone is exopthalmic goitre.

Section – II (40 Marks)
(Attempt any four questions from this section)

Question 2.
(a) Study the diagram given below which represents a stage during the mitotic cell division and answer the questions that follow : [5]

(i) Identify the stage giving suitable reasons.
(ii) Name the parts numbered 1 and 2.
(iii) What is the technical term for the division of nucleus ?
(iv) Mention the stage that comes before the stage shown in the diagram. Draw a neat labelled diagram of the stage mentioned.
(v) Which is the cell division that results in half the number of chromosomes in daughter cells ?
Answer:
(i) The stage is Telophase. The reasons are as follows :
(a) Chromatids thin out in the form of chromatin fibres,
(b) Nucleoli and nuclear membrane reappear,
(c) the cleavage furrow has started deepening.

(ii)

1. Chromosome
2. Nuclear membrane

(iii) The technical term for division on nucleus is Karyokinesis.
(iv) The stage which comes before the stage shown in the diagram is Anaphase.

(v) The cell division that results in half the number of chromosome in daughter cells is meiosis.

(b) Differentiate between the following pairs on the basis of what is mentioned within brackets : [5]
(i) Active Transport and Diffusion [significance in plants]
(ii) Demography and Population density [Definition]
(iii) Antibiotic and Antibody [Source]
(iv) Renal cortex and Renal medulla [Parts of the nephrons present]
(v) NADP and ATP [Expand the abbreviation]
Answer:
(i) Active Transport
Absorption of certain ions which serve as nutrients and maintain high osmotic pressure for absorbing water.

Diffusion
Gaseous exchange across stomata in processes like transpiration, respiration and photosynthesis.

(ii)
Demography
It is the statistical study of human population with reference to size, density, distribution and other vital statistics.

Population density
It is the number of individuals per square kilometre at any given time.

(iii) Antibiotic
Antibiotic are chemical substances produced by certain micro-organisms, e.g. Penicillium produces penicillin.

Antibody
Antibody are special chemicals found in the blood and produced by a type of specialised lymphocytes on exposure to antigens.

(iv) Renal cortex
Malpighian capsule, PCT and DCT lies in renal cortex.

Renal medulla
Loop of Henle lie in the renal medulla.

(v) NADP
Nicotinamide adenine dinucleotide phosphate

ATP
Adenosine triphosphate

Question 3.
(a) The diagram given below represents a plant cell after being placed in a strong sugar solution. Study the diaf’tam and answer the miestions that follow : [5]

(i) What is the state of the cell shown in the diagram ?
(ii) Name the structure that acts as a selectively permeable membrane.
(iii) Label the parts numbered 1 to 4 in the diagram.
(iv) How can the above cell be brought back to its original condition ? Mention the scientific term for the recovery of the cell.
(v) State any two features of the above plant cell which is not present in animal cells.
Answer:
(i) The state of the cell is plasmolysed/extreme flaccidity.

(ii) The structure that acts as a selectively permeable membrane is cell membrane or plasma membrane.

(iii)

1. . – Cell wall
2. – Strong sugar solution
3. – Cell membrane
4. – Nucleus

(iv) The cell can be brought back to its original condition by putting it in a hypotonic environment/ pure water.

(v) The two features present in a plant cell is, (a) presence of large vacuole (b) Chloroplast. These are not present in animal cell.

(b) Give below is a representation of kind of pollution. Study the same and answer the questions that follow: [5]

(i) Name the kind of pollution.
(ii) List any three common sources of this pollution.
(iii) Mention three harmful effects of this pollution on human health.
(iv Explain the term‘Pollutant’.
(v) Name two soil pollutants.
Answer:
(i) The kind of pollution is noise pollution.
(ii) Three common sources of noise pollution are
(a) Industrial machines
(b) Loudspeakers
(c) Automobiles on the street and trains.
(d) Jet aircrafts

(iii) Three harmful effects of noise pollution are :
(a) Disturbs sleep and leads to nervous irritability.
(b) Lowers efficiency of work as it affects concentration of thought.
(c) Prolonged loud noise can lead to deafness as it may damage the ear drum or tympanum.

(iv) A Pollutant is any such constituent which causes pollution, e.g. dust, smoke.

(v) Two soil pollutants
(a) Industrial waste
(b) Chemical fertilizers
(c) Pesticides

Question 4.
(a) The diagram given below represent the relationship between a mouse and a physiological process that occurs in green plants. Study the diagram and answer the questions that follow : [5]

(i) Name the physiological process occurring in the green plant that has kept the mouse alive.
(ii) Explain the physiological process mentioned above.
(iii) Why did the mouse die in bell jar B ?
(iv) What is the significance of the process as stated in (i) for life on earth ?
(v) Represent the above mentioned physiological process in the form of a chemical equation.
Answer:
(i) The physiological process occurring in the green plants is photosynthesis.

(ii) Photosynthesis is a process by which living plant cells containing chlorophyll produce an organic food substance glucose from carbon dioxide and water by using light energy and release oxygen as a by-product.
6CO₂ + 12H₂O C₆H₁₂O₆ + 6H₂O + 6O₂ ↑

(iii) The mouse as well as the burning candle utilised the oxygen present inside the air in the bell jar. Both the processes going on inside the bell jar liberated carbon dioxide. No living organism can survive in an environment of carbon dioxide. So the mouse died.

(iv) The significance of the process is as follows :
(a) Provides food for all organisms – All animals and even human beings depend on plants for food either directly or indirectly. In any food chain the starting point is always a green plant (producer).
(b) Provides oxygen – The life supporting gas oxygen is present in the atmosphere in a free, stable form. This is utilised by living organisms.
(c) Carbon dioxide and oxygen proportion in the atmosphere is maintained.

(b) Mention the exact location of the following : [5]
(i) Prostate gland
(ii) Myelin sheath
(iii) Islets of Langerhans
(iv) Semi-circular canals
(v) Eustachian tube
Answer:
(i) It is present around the urethra when it emerges from the bladder.
(ii) In most neurons the axon is surrounded by a white insulating sheath known as myelin sheath.
(iii) These are special groups of hormone secreting cells present in the entire pancreas.
(iv) It is present in the inner ear in a set of three which are arranged at right angles to each other.
(v) It is present in the middle ear which connects the cavity of the middle ear to the throat.

Question 5.
(a) The diagram shown below is the longitudinal section of a testis of man. Study it carefully and answer the questions that follow : [5]

(i) Label the parts numbered 1 to 3 in the diagram.
(ii) In which part of the testis are the sperms produced ?
(iii) State the functions of the parts labelled 1 and 3 in the diagram.
(iv) Name the cells that secrete Testosterone.
(v) Draw a neat, labelled diagram of a sperm.
Answer:
(i)

1. Scrotum
2. Sperm duct/Vas deferens.
3. Epididymis

(ii) Sperms are produced in the seminiferous tubules.

(iii)

1. The scrotum or scrotal sac is a thin walled maintains a temp of 2 – 3°C less than body temp, for the maturation of the sperm.
2. It helps to store the sperms during which they mature and become motile.

(iv) The cells which secrete testosterone are Leydig cells.

(v)

(b) Give biological reasons for the following statements : [5]
(i) Some woman have facial hair like beard and moustache.
(ii) Cutting of tree should be discouraged.
(iii) In some xerophytes leaves are modified into spines.
(iv) There is frequent urination in winter than in summer.
(v) The left ventricle of the heart has a thicker wall than the right ventricle.
Answer:
(i) In some mature women there can be an overgrowth of the adrenal cortex. This leads to hyper-secretion of cortisone which behave like sex hormone and the women develop certain male characteristics such as beard and moustache.

(ii) Cutting down of trees should be discouraged because deforestation may lead to many problems like droughts, flash flood, soil erosion, extinction of several wild animals and a threat of extinction of hundreds of species. So in order to keep the environment unharmed the cutting of trees should be avoided.

(iii) Xerophytes live in an environment where there is less water or scarcity of water. So in some xerophytes the leaves are modified into spines in order to stop or cut down transpiration. This prevents too much of water loss and saves the plants.

(iv) During winter there is no perspiration. Hence there is less water reabsorption from the glomerular filtrate resulting in more volume of urine. Hence, there is frequent urination in winter than in summer.

(v) The right ventricle pumps blood only to the lungs for oxygenation, whereas the left ventricle pumps blood to the farthest points in the body, like up to the toes in the feet or up to the brain against gravity. So the left ventricle of the heart has thicker walls than the right ventricle.

Question 6.
(a) The diagram given below represents a section of the human heart. Answer the questions that follow : [5]

(i) Which parts of heart are in the diastolic phase ? Give a reason to support your answer.
(ii) Label the parts numbered 1 and 2 in the diagram. What type of blood flows through them ?
(iii) What causes the heart sounds ‘LUBB’ and ‘DUP’ ?
(iv) Name the blood vessels that supply oxygenated blood to the heart muscles.
(v) Draw neat labelled diagrams of a cross section of an artery and a vein.
Answer:
(i) The ventricles of the heart are in diastolic phase because the figure shows flow of blood from auricles to ventricles. Here tricupsid and bicupsid values are open / semilunar values are closed.

(ii)

1. Pulmonary Artery : Type of blood which flow through them are deoxygenated blood.
2. Pulmonary artery : The type of blood which flows through them is oxygenated.

(iii) During ventricular systole the tricuspid and bicuspid valves close with a faint sound known as ‘LUBB’. During venticular diastole the semilunar valves at the roots of aorta and pulmonary artery close with a sharp sound ‘DUP’.

(iv) The blood vessel that supply oxygenated blood to the heart muscles is coronary artery.

(v)

(b) Give appropriate biological/technical terms for the following : [5]
(i) The type of immunity that exists in our body due to our genetic makeup.
(ii) The suppressed allele of a gene.
(iii) The accessory gland in human males whose secretion activates the sperms.
(iv) An apparatus that measures the rate of water uptake in a cut shoot due to transpiration.
(v) The kind of twins fonned from two fertilised eggs.
(vi) A pair of corresponding chromosomes of the same size and shape, one from each parent.
(vii) The mild chemical substance which when applied on the body kills germs.
(viii) The type of waste generated in hospitals and pathological laboratories.
(ix) The antiseptic substance in tears.
(x) Cellular components of blood containing haemoglobin.
Answer:
(i) Innate
(ii) Recessive
(iii) Seminal vesicle
(iv) Potometer
(v) Fraternal twins
(vi) Homologous chromosomes
(vii) Antiseptic
(viii) Biomedical waste
(ix) Lysozyme
(x) Red blood cells/Erythrocyte

Question 7.
(a) In a homozygous pea plant, axial flow’ers (A) are dominant over terminal flowers (a). [5]
(i) What is the phenotype and genotype of the F, generation if a plant bearing pure axial flowers is crossed with a plant bearing pure terminal flowers ?
(ii) Draw a Punnett square board to show the gametes and offsprings when both the parent plants are hetrozygous for axial flowers.
(iii) What is the phenotypic ratio and genotypic ratio of the above cross shown in (ii) ?
(iv) State Mendel’s Law of Dominance.
(v) Name two genetic disorders commonly seen in human males.
Answer:
(i) Phenotype of F₁ – Hyterozygous axial flowers
Genotype of F₁ – Aa (Heterozygous)

(ii)

(iii) Punnett square

Phenotypic ratio – 3 : 1
Genotypic ratio – 1 : 2 : 1

(iv) Law of Dominance states that out of a pair of contrasting characters present together in the F, hybrid, only one is able to express itself while the other remains suppressed. The one that is expressed is the dominant character and the one that is suppressed is the recessive character.

(v) Two genetic disorders commonly in male :
(a) Colour blindness
(b) Haemophilia

(b) The diagram given below is an external view of the human brain. Study the same and answer the questions that follow : [5]

(i) Name the parts labelled A, B and C in the diagram.
(ii) State the main functions of the parts labelled A and B.
(iii) What are the structural and functional units of the brain ? How are the parts of these units arranged in A and C ?
(iv) Mention the collective term for the membranes covering the brain.
(v) What is the function of Cerebrospinal fluid ?
Answer:
(i) A – Cerebrum
B – Cerebellum
C – Spinal cord

(ii) A – controls our thinking, reasoning, memory, consciousness, will power, all voluntary actions and sensory actions.
B – functions to maintain balance of the body and coordinates muscular activity.

(iii) The structural and functional units of the brain is neuron.
The arrangement in A is the axons on the inner side (white matter) and cyton/perikaryon on the outer side (grey matter).
The arrangement in C is the axons on the outer side (White matter) and cy ton/perikaryon on the inner side (grey matter).

(iv) The collective term for the membranes covering the brain is meninges.

(v) The cerebrospinal fluid acts like a (a) cushion to protect the brain from shocks, (b) it also maintains the temperature and pressure inside the brain.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2016 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2016 Solved

Time Allowed : One hour and a half

General Instructions :

Answers to this Paper must be written on the paper provided separately.
You will not be allowed to write during the first 15 minutes.
This time is to be spent in reading the Question Paper,
The time given at the head of this Paper is the time allowed for writing the answers.
Attempt all questions from Section I and any four questions from Section II.
The intended marks for questions or parts of questions are given in brackets [ ].

Section – I (40 Marks)
Attempt all questions from this Section

Question 1.
(a) Name the following:
(i) The exchange of chromatid parts between the maternal and the paternal chromatids of a pair of homologous chromosomes during meiosis.
(ii) The number of individuals inhabiting per unit area.
(iii) The immunity acquired by providing readymade antibodies from outside for treating certain infectious diseases.
(iv) The pollutants that cannot be broken down to simple and harmless products.
(v) The part of the brain that carries impulses from one hemisphere of the cerebellum to the other.
Answer:
(i) Crossing over
(ii) Population Density
(iii) Passive Immunity
(iv) Non biodegradable
(v) Pons varolii

(b) Choose the correct answer from each of the four options given below: [5]
(1) A plant cell may burst when:
(A) Turgor pressure equalises wall pressure.
(B) Turgor pressure exceeds wall pressure.
(C) Wall pressure exceeds turgor pressure.
(D) None of the above
Answer:
(B) Turgor pressure exceeds wall pressure.

(ii) The individual Flattened stacks of membranous structures inside the chloroplasts are known a:
(A) Grana
(B) Stroma
(C) Thylakoids
(D) Cristae
Answer:
(C) Thylakoids

(iii) The nephrons discharge their urine at the:
(A) Urinary bladder
(B) Urethra
(C) Renal pelvis
(D) Renal pyramid
Answer:
(C) Renal pelvis

(iv) Gigantism and Acromegaly are due to :
(A) Hyposecretion of Thyroxine.
(B) Hyposecretion of Growth Hormone.
(C) Hypersecretion of Thyroxine.
(D) Hypersecretion of Growth Hormone.
Answer:
(D) Hypersecretion of Growth Hormone.

(v) The mineral ion needed for the formation of blood clot is:
(A) Potassium
(B) Sodium
(C) Calcium
(D) Iron
Answer:
(C) Calcium

(c) In each set of terms given below, there is an odd one and cannot be grouped in the same category to which the other three belong, identify the odd term in each set and name the category to which the remaining three belong. [5]

Example: Ovary. Fallopian tube. Ureter. Uterus.
Odd term: Ureter
Category: Parts of female reproductive system.
(i) Sewage, Newspaper. Styrofoam, Hay.
(ii) Thymine, Cytosine. Adenine, Pepsin.
(iii) Malleus, Iris. Stapes, Incus.
(iv) Cortisone, Somatotropin, Adrenocorticotropic hormone, Vasopressin.
(v) Typhoid, Haemophilia, Albinism, Colour blindness.
Answer:
(i) Styrofoam, All others are biodegradable pollutants.
(ii) Pepsin, All others are nitrogenous bases present in nucleic acids
(iii) Iris, All others are earossicles
(iv) Cortisone, All others are secreted by the pituitary gland
(v) Typhoid, All others are congenital genetic disorders.

(d) Complete the following paragraph by filling in the blanks (i) to (v) with appropriate words: [5]

The amount of urine output is under the regulation of a hormone called (i) ___________ secreted by the (ii) ___________ lobe of the pituitary gland. If this hormone secretion is reduced, there is an increased production of urine. This disorder is called (iii) ___________ Sometimes excess glucose is passed with urine due to hyposecretion of another hormone called (iv) ___________ leading to the cause of a disease called (v) ___________.
Answer:
(i) Antidiuretic/Vasopressin Hormone
(ii) Posterior
(iii) Diabetes insipidus/Diuresis
(iv) Insulin
(v) Diabetes mellitus

(e) State the exact location of the following structures: [5]

(i) Centromere
(ii) Chordae tendinae
(iii) Thyroid gland
(iv) Ciliary body
(v) Proximal convoluted tubule.
Answer:
(i) Between two sister chromatids of one chromosome
(ii) Attach free margins of bicuspid and tricuspid valves with the papillary muscles
(iii) In front of the neck just below the larynx.
(iv) Extension of the choroid of the eye.
(v) In the cortex region of the kidney between the Malpighian capsule and loop of Henle.

(f) Given below is a diagram depicting a defect of the human eye, study the same and then answer the questions that follow: [5]

(i) Name the defect shown in the diagram.
(ii) What are the two possible reasons that cause this defect?
(iii) Name the type of lens used to correct this defect.
(iv) With the help of a diagram show how the defect shown above is rectified using a suitable lens.
Answer:
(i) Myopia/Near-Sightedness
(ii) Excessive thickening of cornea and increase in the length of eye ball from front to back
(iii) Concave lens
(iv)

(g) Given in the box below are a set of 14 biological terms. Of these, 12 can be paired into 6 matching pairs. Out of the six pairs, one has been done for you as an example. [5]

Example : endosmosis – Turgid cell.
Identify the remaining five matching pairs:

Cushing’s syndrome, Turgid cell, Iris, Free of rod and cone cells, Colour of eyes, Hypoglycemia, Active transport, Acrosome, Addison’s disease, Blind spot, Hyperglycemia, Spermatozoa Endosmosis, Clotting of blood.
Answer:
(i) Cushing’s syndrome : Hyperglycemia
(ii) Free of rod and cone cells : Blind spot
(iii) Colour of eye : Iris
(iv) Hypoglycemia: Addison’s disease
(v) Acrosome: Spermatozoa

(h) State the main function of the following: [5]
(i) Lymphocytes of blood
(ii) Leydig cells
(iii) Lymphocytes of blood
(iv) Eustachian tube
(v) Corpus luteum
Answer:
(i) Production of antibodies to provide specific immunity.
(ii) Secrete male sex hormones called Testosterone
(iii) Help in opening and closing of stomata.
(iv) Act as ventilators to equalize air pressure on the two sides of tympanum.
(v) Secrete progesterone hormone to prepare the uterus for Implantation of Zygote.

Section – II (40 Marks)
Attempt any four questions from this Section

Question 2.
(a) The figure given below is a diagrammatic representation of a part of the cross section of the root in the root hair zone. Study the same and then answer the questions that follow: [5]

(i) Name the parts indicated by the guidelines 1 to 4.
(ii) Which is the process that enables the passage of water from the soil into the root hair?
(iii) Name the pressure that is responsible for the movement of water in the direction indicated by the arrows. Define it.
(iv) Due to an excess of this pressure sometimes drops of water are found along the leaf margins of some plants especially in the early mornings. What is the phenomenon called?
(v) Draw a well labelled diagram of the root hair cell as it would appear if an excess of fertiliser is added to the soil close to it.
Answer:
(i)

1. Root hair
2. Soil particles

(ii) Endosmosis, water potential gradient.
(iii) Osmotic pressure, Root pressure. It is the pressure that develops osmotic system due to osmatic entry of water into it.
(iv) Guttation
(v)

(b) Differentiate between the following pairs on the basis of what is mentioned within brackets : [5]
(i) Human skin cell and Human ovum (number of chromosomes)
(ii) Sperm duct and fallopian tube (function)
(iii) Red Cross and WHO (one activity)
(iv) Rod cells and cone cells (pigment)
(v) LUBB and DUP (names of the valves whose closure produce the sound)
Answer:
(i) Human skin cell (23 pairs) is diploid whereas human ovum (23) is haploid.

(ii) Sperm duct is meant for the passage of sperms from testis to urethra whereas fallopian tubes has funnel shaped opening which receives the mature eggs from the ovary which are carried by it to the uterus.

(iii) WHO is concerned with the strengthening of health services whereas Red Cross is mainly concerned with extending relief and help to the victims of any natural calamity.

(iv) Rod cells contain rhodopsin pigment whereas cone cells contain iodopsin pigment.

(v) LUBB is produced due to the closure of AV valves whereas DUP is produced due to the closure of semi-lunar valves.

Question 3.
(a) Given below is the outline of the human body showing the important glands: [5]

(i) Name the glands marked 1 to 4.
(ii) Name the honnone secreted by part 2. Give one important function of this hormone.
(iii) Name the endocrine part of the part numbered 3.
(iv) Why is the part labelled 1 called the master gland? Which part of the forebrain controls the gland labelled 1 ?
(v) Name the gland that secretes the ‘emergency hormone’.
Answer:
(i)

1. Pituitary gland,
2. Thyroid gland,
3. Pancreas,
4. Adrenal gland

(ii) Thyroxine hormone, it controls basal metabolic rate.
(iii) Islet of Langerhans.
(iv) Pituitary gland is known as the master gland of the body because it controls other endocrine glands by the secretion of trophic hormones. Flour of diencephalon called hypothalamus controls the pituitary gland by the secretion of releasing and inhibiting factors/hormones.
(v) Emergency hormone is secreted by the adrenal gland.

(b) The diagram of an apparatus given below demonstrates a particular process in plants. Study the same and answer the questions that follow: [5]

(i) Name the apparatus.
(ii) Which phenomenon is demonstrated by this apparatus?
(iii) Explain the phenomenon mentioned in (ii) above.
(iv) State two limitations of using this apparatus.
(v) What is the importance of the air bubble in the experiment?
(vi) Name the structures in a plant through which the above process takes place.
Answer:
(i) Ganong’s potometer.
(ii) Rate of transpiration.
(iii) The loss of water in the form of vapours from the aerial exposed parts of a plant is called transpiration.
(iv) The first limitation of this apparatus is that it is very difficult,u to introduce the air bubble at the lower end of the capillary tube. Secondly, various changes in the environment such as, temperature humidity, air velocity etc. may influence the position of air bubble.
(v) Rate of water uptake can be calculated by timing the air bubble movement over a fixed distance on the scale.
(vi) Transpiration takes place through stomata, cuticle and lenticels.

Question 4.
(a)
(i) Draw a well labelled diagram of the membranous labyrinth found in the inner ear. [5]
(ii) Based on the diagram drawn above in (i) give a suitable term for each of the following descriptions:

1. The sensory cells that helps in hearing.
2. The part that is responsible for static balance of the body.
3. The membrane covered opening that connects the middle ear to the inner ear.
4. The fluid present in the middle chamber of cochlea.
5. The structure that maintains dynamic equilibrium of the body.

Answer:
(i)

(ii)

1. of Organs of Corti,
2. uriculus and sacculus,
3. round window,
4. Endolymph,
5. semicircular canal

(b) Give the Biological / technical term for the following: [5]
(i) Complete stoppage of menstrual cycle in females.
(ii) Pigment providing colour to urine.
(iii) The vein which drains the blood from the intestine to the liver.
(iv) The canal through which the testes descend into the scrotum just before the birth of a male baby.
(v) The process causing an undesirable change in the environment.
(vi) The removal of nitrogenous wastes from the body.
(vii) The repeating components of each DNA strand lengthwise.
(viii) An alteration in the genetic material that can be inherited.
(ix) The process of uptake of mineral ions against the concentration gradient using energy from the cell.
(x) Blood vessels carrying blood to the left atrium.
Answer:
(i) Menopause
(ii) Urochrome
(iii) Hepatic portal vein
(iv) Inguinal canal
(v) Pollution
(vi) Excretion
(vii) Nucleotides
(viii) Mutation
(ix) Active transport
(x) Pulmonary veins

Question 5.
(a) The given diagram shows a stage during mitotic division in an animal cell: [5]

(i) Identify the stage. Give a reason to support your answer.
(ii) Draw a neat labelled diagram of the cell as it would appear in the next stage. Name the stage.
(iii) In what two ways is mitotic division in an animal cell different from the mitotic division in a plant cell?
(iv) Name the type of cell division that occurs during:
A. Growth of a shoot
B. Formation of pollen grains.
Answer:
(i) Prophase-Chromosomes have duplicated, nuclear membrane is disappearing, nucleus has disappeared.
(ii) Next stage is Metaphase as shown below :

(iii) Animal cell

1. Asters are formed.
2. Cytokinesis by formation of furrow in the cytoplasm.
3. Occurs in most tissues of the Whole body.

Plant cell

1. Asters are not formed
2. Cytokinesis by cell plate Formation.
3. Occurs mainly at the growing tips and sides

(iv) A-Mitosis and B-Meiosis.

(b) Give scientific reasons for the following statements:
(i) Colour blindness is more common in men than in women.
(ii) Injury to medulla oblongata leads to death.
(iii When an ovum gets fertilized, menstrual cycle stops temporarily in a woman.
(iv) Mature erythrocytes in humans lack nucleus and mitochondria.
(v) Blood flows in arteries in spurts and is under pressure.
Answer:
(i) Colourblindness is more common in men as compared to women because it is a sex-linked and recessive trait. It need two alleles for its expression in women as she contains 2 X-chromosomes whereas only one X-chromosome is present in males, hence a single gene expresses it.

(ii) Injury to medulla oblongata may lead to death as it controls the involuntry actions like breathing movements and beating of heart.

(iii) When fertilization takes place, the corpus luteum is maintained which secretes large amounts of progesterone hormone. This hormone maintains the endometrium of the uterus and prevents its rupturing. Hence, no menstruation takes place.

(iv) Absence of nucleus increases surface area for absorption and transport of O₂ to tissues. No cellular respiration as mitochondria is absent and hence does not use O₂ for itself.

(v) because of the rhythmic ventricular contractions and the narrow lumen of arteries.

Question 6.
(a) The diagram given below is that of a developing human foetus. Study the diagram and then answer the questions that follow: [5]

(i) Label the parts numbered 1 to 3 in the diagram.
(ii) Mention any two functions of the part labelled 2 in the diagram.
(iii) Explain the significance of the part numbered 3 in the diagram.
(iv) Define the term ‘Gestation’. What is the normal gestational period of the developing human embryo?
(v) Mention the sex chromosomes in a male and female embryo.
Answer:
(i) 1-Umbilical cord, 2-Placenta, 3-Amniotic cavity full of amniotic fluid
(ii)

1. Diffusion of O₂ antibodies and nutrients from maternal blood to foetal blood.
2. Diffusion of carbon dioxide, urea, uric acid from foetal blood to maternal blood
3. Acts as a barrier and prevents germs from entering foetal blood
4. Secretes Oestrogen and progesterone

(iii) Amniotic fluid maintains even temeperature around the foetus. It also prevents the foetus from jerks.

(iv) Pregnancy or gestation is the process or period of development of embryo inside the womb of the mother between conception and parturition in viviparous mammals including humans. For humans it is of 40 weeks.

(v) Sex chromosome in male embryo is XY whereas in female it is XX.

(b) The following diagram demonstrates a physiological process taking place in green plants. The whole set up was placed in bright sunlight for several hours. Study the diagram and answer the questions that follow: [5]

(i) What aspect of the physiological process is being examined?
(ii) Explain the physiological process mentioned in (i) above.
(iii) Label the parts numbered 1 and 2 in the diagram.
(iv) Write a well-balanced chemical equation for the physiological process explained in (ii) above.
(v) What would happen to the rate of bubbling of the gas if a pinch of sodium bicarbonate is added to the water in the beaker? Explain your answer.
Answer:
(i) Oxygen is released during photosynthesis.

(ii) Photosynthesis is a physiological process during which green plants synthesize complex organic compounds (Glucose) from simple inorganic compounds- CO₂ and H₂O in the presence of sunlight and chlorophyll.

(iii) 1-Oxygen, 2- aquatic plant
(iv) 6CO₂ + 12H₂O C₆H₁₂O ₆+ 6H₂O + 6O₂
(v) Rate of bubbling will increase by the addition of a pinch of sodium bicarbonate. Plants get more C02, hence rate of photosynthesis increases.

Question 7.
(a) A homozygous tall plant (T) bearing red coloured (R) flowers is crossed with a homozygous dwarf (t) plant bearing white (r) flowers   [5]
(i) Give the genotype and phenotype of the plants of F, generation.
(ii) Mention the possible combinations of the gametes that can be obtained from the F hybrid plant.
(iii) State the Mendel’s law of Independent Assortment.
(v) Mention the phenotypes of the offsprings obtained in F₂ generation.
(vi) What is the phenotypic ratio obtained in F₂ generation?
Answer:
(i) Genotype of F₁ plants : TtRr and the Phenotype will be Tall and red flowered.
(ii) The possible combination of gametes of F₁ plants TR, Tr, tR and tr.

(iii) Mendel’s law of independent assortment states that the factors or genes controlling different characters assort independently without influencing each other during the formation of gametes.

(iv) Phenotypes in F₂ generation:
Tall plants with red flowers, Tall plants with white flowers, Dwarf plants with red flowers and Dwarf plants with white flowers’

(v) Phenotypic ratio in F₂ generation : 9 : 3 : 3 : 1

(b) Briefly explain the following terms: [5]
(i) Reflex action
(ii) Power of accommodation
(iii) Photophosphorylation
(iv) Hormone
(v) Synapse
Answer:
(i) Reflex action is the spontaneous, automatic and stereotyped response to stimuli without consulting the will power.
(ii) Ability of the eye to see the object equally clear from various distances is called Power of accommodation.

(iii) Photophosphorylation is the synthesis of ATP from ADP and phosphate that occurs in a plant using radiant energy absorbed during photosynthesis.

(iv) Hormone is a regulatory substance produced in an organism and transported in tissue fluids such as blood or sap to stimulate specific cells or tissues into action.

(v) Close proximity between the terminal arborization of axon of one neuron and the dendrons of another neuron without any physical contact is called synapse.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2014 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2014 Solved

Time: 1 1/2 hour
Maximum Marks: 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section-I (40 Marks)
(Attempt all questions from this Section)

Question 1.
(a) Name the following :
(i) The part of the brain associated with memory.
(ii) The ear ossicle which is attached to the tympanum.
(iii) The type of gene, which in the presence of a contrasting allele is not expressed.
(iv) The hormone secreted by islets of langerhans.
(v) The process of conversion of ADP into ATP during photosynthesis. [5]
Answer:
(i) Cerebrum
(ii) Malleus/Hammer
(iii) Recessive gene
(iv) Insulin, Glucagon.
(v) Photophosphorylation

(b) State the main function of the following :
(i) Cerebrospinal fluid.
(ii) Eustachian tube.
(iii) Suspensory ligament of the eye.
(iv) Sperm duct.
(v) Linticels. [5]
Answer:
(i) Provide mechanical protection to brain/provide nourishment to brain.
(ii) Maintain/Equalize air pressure on either sides of the ear drum.
(iii) Hold the lens in position.
(iv) Transport sperm from the epididymis to penis for discharge.
(v) To facilitate transpiration in older stem.

(c) Copy and complete the following by filling the blanks 1 to 5 with appropriate words :
The human female gonads are ovaries. A maturing egg in the ovary is present in a sac of cells called …… (1). As the egg grows larger, the follicle enlarges and gets filled with a fluid and is now called the …………. (2) follice. The process of releasing the egg from the ovary is called ……… (3). The ovum is picked up by the oviducal funnel and fertilization takes place in the …….. (4). In about a week the blastocyst gets fixed in the endometrium of the uterus and this
process is called …… (5).
Answer:
The human female gonads are ovaries. A maturing egg in the ovary is present in a sac of cells called follicle (1). As the egg grows larger, the follicle enlarges and gets filled with a fluid and is now called the Graafian (2) follice. The process of releasing the egg from the ovary is Called ovulation (3). The ovum is picked up by the oviducal funnel and fertilization takes place in the oviduct (4). In about a week the blastocyst gets fixed in the endometrium of the uterus and this process is called implantation (5).

(d) Given below are six sets with four terms each. In each set one term is odd and cannot be grouped in the same category to which the other three belong. Identify the odd one in each set and name the category to which the remaining three belong. The first one has been done as an example.
Example : Calyx, Corolla, Stamens, Midrib
Odd term : midrib
Category : parts of a flower.
(i) Haemoglobin, Glucagon, Iodopsin, Rhodopsin.
(ii) Urethra, Uterus, Urinary bladder, Ureter.
(iii) Transpiration, Photosynthesis, Phagocytosis, Guttation.
(iv) Cyton, Photon, Axon, Dendron.
(v) Oxytocin, Insulin, Prolactin, Progesterone. [5]
Answer:
Odd term : Glucagon
Category : Pigments
(ii) Odd term: Uterus
Category : Parts of excretory system
(iii) Odd term : Phagocytosis
Category : Processes taking place in plants
(iv) Odd term : Photon
Category : Parts of a neuron.
(v) Odd term : Insulin
Category : Female hormones.

(e) The figure given below represents an experimental set up with a weighing machine to demonstrate a particular process in plants. The experimental set up was placed in bright sunlight. Study the diagram and answer the following questions :

(i) Name the process intended for study.
(ii) Define the above mentioned process.
(iii) When the weight of the test tube (A and B) is taken beofre and after the experiment, what is observed? Give reasons to justify your observation in A and B.
(iv) What is the purpose of keeping the test tube B in the experimental set up?
Answer:
(i) Transpiration.
(ii) It is the process in which water is lost in the form of vapour from the aerial parts of the plant.
(iii) After the experiment, we observe test tube A is raised up i.e., a loss of weight. In test tube B, the weight remains unchanged.
Reason : In test tube A, loses weight due to the plant transpires and loses water. In B there is no plant so there is no transpiration and the oil on the surface prevents direct evaporation and so weight remains unchanged.
(iv) It acts as a Control Set Up.

(f) Match the items given in Column A with the most appropriate ones in Column B and rewrite the correct matching pairs from Column A and Column B :

Answer:

(f)

Column A	Column B
1. Pituitary gland	c. Growth hormone
2. Sulphur dioxide	d. Acid rain
3. Seminiferous tubules	e. Sperms
4. Clotting of blood	b. Calcium
5. Guttation	h. Hydathodes

(g) Choose the correct answer from the four options given below:

(i) Cretinism and Myxoedema are due to:
A. Hyper secretion of thyroxin
B. Hyper secretion of growth hormone
C. Hyposecret ion of thyroxin
D. Hyposecretion of growth hormone.
Answer:
(C) Hyposecretion of thyroxine.

(ii) Which of the following is not a natural reflex action?
A. Knee-jerk.
B. Blinking of eyes due to strong light
C. Salivation at the sight of food
D. Sneezing when any irritant enters the nose.
Answer:
(C) Salivation at the sight of food.

(iii) After mitotic cell division, a female human cell will have:
A. 44 + xx chromosome.
B. 44 + xy chromosome
C. 22 + x chromosome
D. 22 + y chromosome.
Answer:
(A) 44 + xx chromosome.

(iv) The antibiotic penicillin is obtained from:
A. Protozoan
B. Bacteria
C. Virus
D. Fungus
Answer:
(D) Fungus.

(v) The site of maturation of human sperms is the :
A. Seminiferous tubule
B. Interstitial cells
C. Epididymis
D. Prostate gland.
Answer:
(C) Epididymis.

(h) State the exact location of the following:
(i) Tricuspid value.
(ii) Amnion.
(iii) Yellow spot.
(iv) Seminal vesicle
(v) Adrenal gland.
Answer:
Exact location :
(i) Tricuspid value : Between right auricle and right ventricle.
(ii) Amnion : Around the foetus in the uterus.
(iii) Yellow spot: Centre of horizontal axis of eye bail on retina.
(iv) Seminal vesicle : Between posterior surface of the urinary bladder and rectum in male,
(v) Adrenal gland : Above each kidney fitted like a cap.

(b) State the exact location of the following :
(i) Tricuspid value.
(ii) Amnion.
(iii) Yellow spot.
(iv) Seminal vesicle
(v) Adrenal gland.
Answer.
(a) (i) Cerebrum
(ii) Malleus/Hammer
(iii) Recessive gene
(iv) Insulin, Glucagon.
(v) Photophosphorylation.

 

Section-II (40 Marks)
(Attempt any four questions from this section)

Question 2.
(a) Differentiate between the following pairs on the basis of what is mentioned within brackets :
(i) Spinal nerves and Cranial nerves (Number of nerves)
(ii) Near vision and Distant Vision (shape of the eye lens)
(iii) Corpus callosum and Corupus luteum. (function).
(iv) Turgor pressure and wall pressure. (Explain).
(v) Disinfectant and Antiseptic (Definition). [5]
Answer:
(i) Spinal nerves : 31 pairs.
Cranial nerves : 12 pairs.
(ii) Near vision : More convex/too curved,
Distant vision : Less convex/too flat.
(iii) Corpus callosum : Transmitting impulses from one cerebral hemisphere to other.
Corpus luteum : Secrete female sex hormones Oestrogen and progesterone.
(iv) Turgor pressure : The pressure exerted by cell contents of a turgid cell on the cell wall.
Vall pressure : The pressure exerted by the wall of a turgid cell on the cell contents.
(v) Disinfectant : These are chemicals of strong concentration applied on spots and areas to kill germs.
Antiseptic : These are chemicals of mild concentration applied on the body to kill germs or harmful microbes.

(b) The diagram below represents the simplified pathway of the circulation of blood. Study the same and answer the questions that follow :

(i) Name the blood vessels labelled 1 and 2.
(ii) State the function of blood vessels labelled 5 and 8.
(iii) What is the importance of the blood vessel labelled 6?
(iv) Which blood vessel will contain a high amount of glucose and amino acids after a meal?
(v) Draw a diagram of the different blood cells as seen in a smear of human blood. [5]
Answer:
(i) (1) Anterior/Superior venacava.
(2) Aorta.
(ii) Function of 5 : Supply oxygenated blood from Aorta to liver.
Function of 8 : Carry deoxygenated blood from posterior parts of the body to the right auricle of heart.
(iii) Importance of the blood vessel labelled 6 : Blood vessel 6 is called 1-lepatic portal vein, it carries deoxygenated blood from intestine to liver. This blood contains excess glucose, some toxic substances etc. which are sent to liver where they are detoxified and the excess glucose is converted to glycogen and stored. This prevents these substances from directly entering the heart and damaging the heart.
(iv) Hepatic Portal Vein
(v)

Question 3.
(a) A candidate in order to study the process of osmosis has taken 3 potato cubes and put them in 3 different beakers containing 3 different solutions. After 24 hours, in the first beaker the potato cube increased in size, in the second beaker the potato cube decreased in size and in the third beaker there was no change in the size of the potato cube. T he following diagram shows the result of the same experiment:

(i) Give the technical terms of the solution used in beakers, 1, 2 and 3.
(ii) In beaker 3 the size of the potato cube remains the same. Explain the reason in brief.
(iii) Write the specific feature of the cell sap of root hairs which helps in absorption of water.
(iv) What is osmosis?
(v) How does a cell wall and a cell membrane differ in their permeability? [5]
Answer:
(i) (1) Hypotonic solution.
(2) Hypertonic solution.
(3) Isotonic solution.
(ii) In beaker 3, the concentration of potato cube and the medium is same. So there is no osmosis taking place therefore the size of cube remains same.
(iii) The concentration of cell sap is higher in the root hair as compared to soil water due to endosmoses is taken place facilitating absorption of water.
(iv) Osmosis is a process of flow of solvent molecules from lower concentration to higher concentration through a semipermeable membrane.
(v) Cell wall is freely permeable and cell membrane is semi-permeable.

(b) A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
(i) What aspect of photosynthesis was being tested?
(ii) Why was the plant placed in the dark before beginning the experiment?
(iii) During the starch test why was the leaf:
(1) boiled in water.
(2) boiled in methylated spirit.
(iv) Write a balanced chemical equation to represent the process of photosynthesis.
(v) Draw a neat diagram of a chloroplast and label its parts. [5]
Answer.
(i) Sunlight is necessary for photosynthesis.
(ii) To make the leaves free from starch.
(iii) (1) To kill the cells.
(2) To remove the chlorophyll.
(iv)

(v)

Question 4.
(a) The diagram given below is a representation of a certain phenomenon pertaining to the nervous system. Study the diagram and answer the following questions :

(i) Name the phenomenon that is being depicted.
(ii) Give the technical term for the point of contact between the two nerve cells.
(iii) Name the parts 1, 2, 3 and 4.
(iv) Write the functions of parts 5 and 6.
(v) How does the arrangement of neurons in the spinal cord differ from that of the brain? [5]
Answer:
(i) Reflex action.
(ii) Synapse
(iii) (1) Sensory neuron / Afferent fibre.
(2) Dorsal ganglion / Dorsal root.
(3) White matter
(4) Gray matter
(iv) Function of 5 (Synape) : Tiansmit the sensory impulse from sensory neuron to the motor neuron.
Function of 6 (Motor neuron/Efferent neuron): Transmit the command to the effectors (muscle or glands).
(v) In Spinal cord : Cytons are in the inner grey matter and Axons in the outer white matter.
In Brain : Cytons are in the outer grey matter and Axons in the inner white matter.

(b) Give scientific reasons for the following statements :
(i) Use of C.F.C. is banned in many countries.
(ii) We cannot distinguish colours in moonlight.
(iii) Balsam plants wilt during midday even if the soil is well watered.
(iv) Carbon monoxide is highly dangerous when inhaled.
(v) A person after consuming alcohol walks clumsily. [5]
Answer.
(i) Chlorifluorocarbons (CFC) are one of the major cause for ozone depletion.
(ii) Moonlight is dimlight during which cone cells of our eye do not function well therefore colour is not perceieved. It is only red cells that function in moonlight.
(iii) It. is a herbaceous plant and loses too much of water by excessive transpiration. The rate of transpiration is more than the rate of absorption. So they with weak stem droops and wilts.
(iv) Carbon monoxide has great affinity with haemoglobin of our blood. It mixes with haemoglobin almost 300 times more than that with oxygen. It cuts off the supply of oxygen due to which it is fatal.
(v) Alcohol affects the cerebellum part of the brain which is responsible for muscular co-ordination. So after consuming alcohol due to lack of muscular balance and co-ordination, the person walks clumisly.

Question 5.
(a) Give below is a diagram representing a stage during mitotic cell division. Study it carefully and answer the questions that follow :

(i) Is it a plant cell or an animal cell? Give a reason to support your answer.
(ii) Identify the stage shown.
(iii) Name the stage that follows the one shown here. How is that stage identified?
(iv) How will you differentiate between mitosis and meiosis on the basis of the chromosome number in the daughter cells?
(v) Draw a duplicated chromosome and label its parts. [5]
Answer:
(i) Plant cell. Because Cell wall present and Centrioles absent.
(ii) Prophase.
(iii) Metaphase. Chromosomes are arranged in the equitorial plane of the cell.
(iv) In Mitosis : The chromosome number in daughter cell is same as that of the mother cell
i.e., diploid mother cell gives rise to 2 diploid daughter cells.
In Meiosis : The chromosome number ¡s halved in the daughter cells i.e., the diploid mother cell gives rise to four haploid daughter cells.
(v)

(b) (i) Name the disease for which the following of vaccines are given :
(1) Salk’s Vaccine.
(2) B.C.G

(ii) Give one example of each of the following:
(1) A water pollutant.
(2) An aquatic plant used in the lab to demonstate O₂ liberation during photosynthesis.
(3) An antibiotic.
(4) A nitrogenous base in DNA.

(iii) Expand the following biological abbreviations:
(1) ATP
(2) TSH
(3) DPT
(4) DNA [5]
Answer:
(1) Poliomyelitis.
(2) Tuberculosis.
(ii)
(1) Chemicals like Mercury from Industries / Sewage / detergents
(2) Hydrilla.
(3) Penicillin.
(4) Adenine.
(iii) (i) ATP : Adenosine triphosphate.
(2) TSH : Thyroid stimulating hormone.
(3) DPT: Diphtheria Pertussis Tetanus.
(4) DNA : Deoxyribo Nucleic acid.

Question 6.
(a) The given diagram represents a nephron and its blood supply. Study the diagram and answer the following questions :

(i) Label parts 1, 2, 3 and 4.
(ii) State the reason for the high hydrostatic pressure in the glomerulus.
(iii) Name the blood vessel which contains the least amount of urea in this diagram.
(iv) Name the two main stages of urine formation.
(v) Name the part of the nephron which lies in the renal medulla. [5]
Answer:
(1) Collecting duct.
(2) Distal convoluted tubule.
(3) Loop of Henle.
(4) Bowman’s capsule.
(ii) Afferent arteriole is wider than efferent artiriole.
(iii) Blood vessel 6-Efferent arteriole that connects to renal vein.
(iv) (1) Ultrafiltration.
(2) Selective Reabsorption.
(v) Loop of Henle.

(b) Briefly explain the following terms :
(i) monohybrid cross.
(ii) Biomedical waste.
(iii) Innate immunity.
(iv) Diapedesis.
(v) Hormones. [5]
Answer.
(i) Monohybrid Cross : A cross between two parents taking the alternative traits of one single character. For example, a cross between tall and dwarf pea plants.
(ii) Wastes containing dressings, amputated body parts, used surgical instruments etc. from hospitals, that spread diseases.
(iii) Innate immunity is the immunity that a person inherits from his parents i.e., the person is born with it.
(iv) The process by which white blood cells squeeze out through the walls of capillaries to reach the site of infection.
(v) Hormones : Chemical substance produced by endocrine gland and poured into blood to act on target organs.

Question 7.
(i) (i) State any two harmful effects of noise pollution on human health.
(ii) Categorize the following activities as per the functions of the Red Cross Society and the WHO:
(1) To suggest quarantine measures to prevent spread of disease.
(2) Humanitarian services to victim of war.
(3) To educate people in accident prevention.
(4) To promote projects for research on disease.
(iii) Write any two major reasons for the population explosion in India.
(iv) State Mendel’s Law of segregation. [5]
Answer:
(i) Two harmful effects of noise pollution :
(1) Cause hearing disorder.
(2) Cause high blood pressure.
(ii) (1) WHO
(2) Red Cross
(3) Red Cross
(4) WHO
(iii) (1) Desire for a male child.
(2) Illiteracy and lack of awareness about birth control measures.
(iv) This law states that in a monohybrid cross, the contrasting characters or factors separate/ or segregate from each other at the time of gamete formation.

(b) Give technical terms for the following :
(i) A method of contraception in which the sperm duct is cut and ligated.
(ii) Statistical study of human population.
(iii) The protective covering of the heart.
(iv) A sudden heritable change in the gene.
(v) Repeated units of DNA molecule.
(vi) The fluid portion of blood.
(vii) The nerve that transmits impulses from the ear to the brain.
(viii) Group of hormones which influence other endocrine glands to produce hormones.
(ix) Thin walled sac of skin that covers the testes.
(x) The permanent stoppage of the menstrual cycle in a woman aged 50 years. [5]
Answer.
(i) Vasectomy
(ii) Demography
(iii) Pericardium
(iv) Mutation
(v) Nucleotide
(vi) Plasma
(vii) Auditory nerve
(viii) Tropic hormones
(ix) Scrotum
(x) Menopause.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2013 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2013 Solved

Time: 1 1/2 hour
Maximum Marks: 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section-I (40 Marks)
(Attempt all questions from this Section)

Question 1.
(a) Name the following :
(i) The cell body of a nerve cell.
(ii) The waxy layer on the epidermis of the leaf meant to reduce transpiration.
(iii) A non-biodegradable pesticide.
(iv) The physical expression of genes in an individual.
(v) Knot-like mass of blood capillaries inside the bowman’s capsule. [5]
Answer:
(i) Perikaryon or cyton
(ii) Cuticle
(iii) D.D.T., B.H.C.
(iv) Phenotype
(v) Glomerulus/Glomerular capillaries

(b) State the exact location of the following :
(i) Chloroplast.
(ii) Incus.
(iii) Corpus callosum.
(iv) Guard cells.
(v) Pulmonary semilunar valve. [5]
Answer:
Exact location:
(i) Mesophyll cells between upper and lower epidermis and palisade and spongy cells of leaves.
(ii) Bone in middle ear.
(iii) In cerebrum part of brain.
(iv) In stoma of leaves.
(v) This valve is located at the opening of right ventricle into the pulmonary artery.

(c) Give below are six sets with four terms each. In each set a term is an oldd one and cannot be grouped in the same category to which the other three belong. Identify the odd one in each set and name the category to which the remaining three belong. The first one has been done as an example:
Example : Fructose, Sucrose, Glucose, Calcium.
Odd term: Calcium
Category : Carbohydrates.
(i) Cabonic acid, Acetic acid, benzoic acid, boric acid.
(ii) Saliva, bile, sweat, tears.
(iii) Cretinism, Myxedema, Simple goitre, Acromegaly.
(iv) Sneezing, coughing, blinking, typing.
(v) Semicircular canals, Cochlea, tympanum, utriculus. [5]
Answer:
Odd one out:
(i) Odd term : Boric acid
Category : Inorganic acid, organic acids (all others)
(ii) Odd term : Bile
Category : Germ killing secretions of our body (all others)
(iii) Odd term : Acromegaly
Category : Due to malfunctioning of thyroid gland (all others)
(iv) Odd term : Typing
Category : Natural (inborn) Reflex
(v) Odd term : Tympanum
Category : Part of inner ear (parts of inner ear all others)

(d) Match the items in Column A with that which is most approriate in Column B. Rewrite the matching pair.

Column A	Column B
(1) Testis	(a) Kidney
(2) Poliomyelitis	(b) water vapour
(3) Transpiration	(c) Prostate gland
(4) Clotting of Blood	(d) Iron
(5) Uriniferous tubule	(e) Uterus
	(f) Gonad
	(g) Salk’s vaccine
	(h) water droplet
	(i) Calcium
	(j) TAB vaccine

Answer:

Column A	Column B
(1) Testis	(f) Gonad
(2) Poliomyelitis	(g) Salk’s vaccine
(3) Transpiration	(b) water vapour
(4) Clotting of blood	(i) calcium
(5) Uriniferous tubule	(a) kidney

(e) Choose the correct answer from the four options given below :

(i) The cell component visible only during cell division.
A. Mitochondria
B. Chloroplast
C. Chromosome
D. Chromatin.
Answer:
C. Chromosome

(ii) Pulse wave is mainly caused by the :
A. Systole of atria
B. Diastole of atria.
C. Systole of the left ventricle.
D. Systole of the right ventricle.
Answer:
C. Systole of the left ventricle

(iii) The recessive gene is one that expresses itself in :
A. Heterozygous condition
B. Homozygous condition
C. F₂ generation
D. Y-linked inheritance.
Answer:
B. Homozygous condition

(iv) A gland which secretes both hormone and enzyme is the :
A. Pituitary
B. Pancreas
C. Thyroid ‘
D. Adrenal
Answer:
B. Pancreas

(v) The ventral root ganglion of the spinal cord contains cell bodies of the :
A. Motor neuron
B. Sensory neuron
C. Intermediate neuron
D. Association neuron. [5]
Answer:
B. Sensory neuron

(f) Given below is an example of certain structures and their special functional activities.
For example : Eye and vision. On a similar pattern complete the following :
(i) Neutrophils : ……………
(ii) Ureter : …………..
(iii) Neuro transmitters : …………
(iv) Iris of the eye : ……….
(v) Placenta : ……… [5]
Answer:
Functional activities :
(i) Phagocytosis
(ii) Ureter : Passes the urine from kidney to urinary bladder.
(iii) Neurotransmitters : The end portion of axon have swollen ends like bulbs which store chemicals called neurotransmitters and help in transmission of nerve impulse.
(iv) Iris of the eye : Regulates the amount of light entering the eye.
(v) Placenta : It is the link between the mother and the foetus (embryo).

(g) The figure given below represents an experiment to demonstrate a particular aspect of photosynthesis. The alphabet ‘A’ represents a certain condition inside the flask.

(i) What is the aim of the experiment ?
(ii) Identify the special condition inside the flask.
(iii) Name an alternative chemical that can be used instead of KOH.
(iv) In what manner do the leaves 1 and 2 differ at the end of the starch test ? [5]
Answer:
(i) Aim : Carbon dioxide is necessary for photosynthesis.
(ii) Flask must have KOH solution to absorb CO₂.
(iii) Lime water.
(iv) Leaf 2 which has exposed to atomspheric air becomes blue black and leaf 2 will not become blue black.

(h) Given below are five groups of terms. In each group arrange and rewrite the terms in the correct order so as to be in a logical sequence.
For example :
Question : Implantation, Parturition, Ovulation, Gestation, Gertilization.
Answer: Ovulation, Fertilization, Implantation, Gestation, Parturition.
(i) Spongy cells, Upper epidermis, Stoma, Palisade tissue, Substomatal space.
(ii) Spinal cord, Motor neuron, Receptor, Effector, Sensory neuron.
(iii) Endodermis, Cortex, Soil water, Xylem, Root hair.
(iv) Metaphase, Telophase, Prophase, Anaphase, Cytokinesis.
(v) Intestine, Liver, Intestinal artery, Hepatic Vein, Hepatic Portal Vein. [5]
Answer:
Arrange the terms :
(i) Upper epidermis, Palisade tissue, Spongy cells, Substomatal space, Stoma.
(ii) Receptor, Sensory neuron, Spinal cord, Motor neuron, Effector.
(iii) Soil water, Root hair, Cortex, Endodermis, Xylem.
(iv) Prophase, Metaphase, Anaphase, Telophase, Cytokinasis.
(v) Intestinal artery, Intestine, Hepatic Portal Vein, Liver, Hepatic Vein.

Section-II (40 Marks)
(Attempt any four questions from this section)

Question 2.
(a) Given below is a diagram of the lateral section of a testis of a man. Study the same and answer the questions that follow :

(i) Label the parts numbered 1 to 4 of the diagram.
(ii) State the functions of the parts labelled 1 and 3.
(iii) What is the significance of the testis being located in the scrotal sac outside the abdomen?
(iv) What is the role played by the inguinal canal ?
(v) What is semen ? [5]
Answer:
(a)
(i)

1. Seminiferous tubule
2. Lobule
3. Epididymis
4. Sperm duct

(ii) Function of Part 1 :
In seminiferous tubule the sperms are produced.
Function of Part 3 :
Epididymis stores the sperms for some days during which they mature and become motile.

(iii) Since maturation of sperm takes place 2° to 3° lower than the body temperature hence located in the scrotal sac outside the abdomen.
(iv) Inguinal canal allows the descent of testis along with their ducts blood vessels nerves etc.
(v) Semen : Seminal vesicles, prostate gland, cowper’s glands add their secretions to the sperms and collectively form milky fluid the semen.

(b) Give the biological/technical terms for the following :
(i) Chemicals found in the blood which act against antigens.
(ii) A constituent that causes pollution.
(iii) The onset of menstruation in a young girl.
(iv) Structure which connects the placenta with the foetus.
(v) The fluid present between the layers of meninges.
(vi) Permanently open structures seen on the bark of an old woody stem.
(vii) The biological process which is the starting point of the food chain.
(viii) The change in an organism resulting due to stimulus.
(ix) An Antiseptic substance present in tears.
(x) A solution in which the relative concentration of water molecules and the solute on either side of the cell membrane is the same. [5]
Answer:
(i) Antibodies produced by lymphocytes
(ii) CO₂, SO₂, CO
(iii) Menarche
(iv) Umbilical Cord
(v) Cerebrospinal fluid
(vi) Lenticels
(vii) Photosynthesis
(viii) Response
(ix) Lysozyme
(x) Isotonic

Question 3.
(a) Draw a diagram of the human eye as seen in a vertical section and label the parts which suits the following descriptions relating to the :
(i) photosensitive layer of the eye.
(ii) structure which is responsible for holding the eye lens in its position.
(iii) structure which maintains the shape of the eye ball and the area of no vision.
(iv) anterior chamber seen in front of the eye lens.
(v) Outer most transparent layer seen in front of the eye ball. [5]
Answer:

(i) Retina.
(ii) Suspensary ligament.
(iii) Vitreous chamber
(iv) Aqueous chamber.
(v) Conjunctiva.

(b) Differentiate between the following pairs on the basis of what is mentioned within brackets :
(i) Photolysis and Photophosphorylation. (Definition)
(ii) Bicuspid valve and Tricuspid valve. (Function)
(iii) Vasectomy and Tubectomy. (Explain)
(iv) Cerebrum and Spinal cord. (Arrangement of nerve cells)
(v) Bowman’s capsule and Malpighian capsule, (parts included) [5]
Answer.
(i) Photolysis : Splitting of water by the action of light during photosynthesis.
Photophosphorylation : Addtion of phosphate (phosphoryl) group to a molecule such as ADP to ATP.
(ii) Bicuspid and tricuspid valves regulate the flow of blood in a single direction.
(iii) Vasectomy : It is a surgical method for female for population control. In this method abdomen is opened and the fallopian tubes (oviducts) are cut or tied with nylon thread to close the passage of the egg.
Tubectomy : This is the surgical method in male for population control. In this surgery a small cut is made in scrotum, vas deferens (sperm duct) is ligated and small piece between the two ligatures is removed. This surgery is easier, quicker and safer.
(iv) Cerebrum and spinal cord (arrangement of nerves).
Cerebrum : Inner portion of cerebrum consists of white matter’ which mainly contains the axons (nerve fibres) of the neuron.
The outer portion of cerebrum contains cell bodies of neurons is called ‘gray matter’. Spinal cord : In spinal cord arrangement of white and gray matter is reversed from that in brain.
(v) Bowman’s Capsule : It is a rounded, cup-shaped body.
Malpighian Capsule : The Bowman’s capsule and the glomerulus together are called Malpighian capsule.

Question 4.
(a) Given below is a schematic diagram showing Mendel’s Experiment on sweet pea plants having axial flowers with round seeds (AARR) and Terminal flowers with wrinkled seeds (aarr). Study the same and answer the questions that follow :

(i) Give the phenotype of F₁ progeny.
(ii) Give the phenotypes of F₂ progeny produced upon by the self-pollination of F₁ progeny.
(iii) Give the phenotypic ratio of F₂ progeny.
(iv) Name and explain the law induced by Mendel on the basis of the above observation. [5]
Answer:
(i) F₁ Progeny — Axial Round
(ii)

(iii)

(iv) Law of independent assortment. When there are two pairs of contrasting characters the distribution of the members of one pair into the gamete is independent of the distribution of the other pair.

(b) Complete the following table by filling in the blanks from 1 to 10 with appropriate terms :
[5]
Answer.

Question 5.
(a) The diagram given below represents the human heart in one phase of its functional activities. Study the same and answer the questions that follow :

(i) Name the phase.
(ii) Label the parts 1, 2 and 3.
(iii) Which part of the heart is contracting in this phase ? Give a reason to support your answer.
(iv) Draw well labelled diagrams of part 1 and 2 to show the structural differences between them. [5]
Answer:
(i) Phase : Auricular systole.
(ii)

1. Pulmonary artery (to the left lung)
2. Superior vena cava
3. Aorta

(iii) Auricles are contracting in this phase because bicuspid (operative) and tricuspid values (operative) are open to allow the blood to flow from auricles to ventricles.

(iv)

(b) Give biological reasons for the following:
(i) The wall of the ventricle is thicker than the auricles.
(ii) The renal cortex has a dotted appearance.
(iii) Wooden frames of doors get jammed during the monsoon season.
(iv) Throat infections can lead to ear infections.
(v) The hand automatically shows the direction to turn a cycle without thinking. [5]
Answer:
(i) Walls of ventricle is thicker because they have to pump blood to long distance.
(ii) Each human kidney possesses about one million of functional and structural units known as nephrons or kidney tubules.
(iii) Wooden doors get jammed during monsoon season because of imbibition substance which are made up of cellulose are hydrophilic.
(iv) Throat infection can lead to ear infection due to the link of nasolacrimal duct between both.
(v) Hand automatically show the direction due to conditioned (Acquired) reflexes.

Question 6.
(a) The figure given below shows the epidermal cells of an onion bulb. This cell was then transferred to a drop of sugar solution.

(i) Draw a well labelled diagram of the epidermal cell as it would appear after immersion in a strong sugar solution.
(ii) What scientific term is used for the changes as shown in (i) above ?
(iii) What should be done to resotre the cell back to its original condition ?
(iv) Give the scientific term for the recovery of the cell as a result of the step taken in (iii) above.
(v) Define the term osmosis. [5]
Answer:

(i) Cytoplasm will shrink and plasma membrane will withdraw from cell wall.
(ii) Plasmolysis.
(iii) Cell is to be placed in distilled water.
(iv) Deplasmolysis.
(v) Osmosis is the diffusion of water molecule across semipermeable membrane from a more dilute solution to less dilute solution.

(b) Briefly explain the following terms :
(i) Genes.
(ii) Cytokinesis in plant cells.
(iii) Guttation.
(iv) Diabetes insipidus.
(v) disinfectants.
Answer:
(i) Genes : The specific part of chromosomes which are composed of D.N.A. Genes determine hereditary characters that transfer from parents to offsprings.
(ii) Cytokinesis in plant cells : A cell plate is laid down in the cytoplasm at equatorial plane.
(iii) Guttation : Guttation is the loss of water as droplet along the margins of leaves through hydathodes. e.g. Banana, strawberry.
(iv) Diabetes insipidus : When concentration of glucose decrease in the blood as well as in urine due to hypersecretion of insulin.
(v) Disinfectants : Strong chemical sulestances that are applied on spots and places where germs thrive and multiply, e.g. Phenol, lysol, lime, 40% formalin.

Question 7.
(a) (i) Draw a well labelled diagram to show the anaphase stage of mitosis in a plant cell having four chromosomes.
(ii) State any two harmful effects of acid rain.
(iii) Expand the following biological abbreviations :
(1) NADP,
(2) ACTH [5]
Answer:

(a) (i)

(ii) Acid rain is caused due to pollutant gases CO₂, SO₂, CO causing much danger to agricultural crops and stone monuments.

(iii) (1) NADP : Nicotinamide Adenine Dinucleotide Phosphate.
(2) ACTH: Adrenocorticotropic.

(b) (i) List any two major activities of the Red Cross.
(ii) Write any two major reasons for the population explosion in the world.
(iii) Write the names of our nitrogenous bases in a DNA molecule. [5]
Answer:
(i) (1) Red cross extend relief and help to the victims of any calamity – flood, fire, famine, earthquakes etc.
(2) To extend all possible first aid in any accident.
(ii) Two major reasons for population growth in world are illiteracy, traditional beliefs, social customs and low marriage age.
(iii) These bases are as follow :
Adenine (A), Guanine (G), Thymine (T) and Cytosine (C)

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2019 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2019 Solved

Time : (One hour and a half)

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section – I (40 Marks)
(Attempt all questions from this Section)

Question 1.
(a) Name the following :
(i) The layer of the eyeball that provides nourishment to the eye.
(ii) One gaseous compound which depletes the ozone layer.
(iii) The structure which connects the placenta and the foetus.
(iv) A pair of corresponding chromosomes of the same shape and size and derived one from each parent.
(v) The compound formed when haemoglobin combines with carbon dioxide in blood.
Answer:
(i) Choroid
(iii) CFC’s (chlorofluorocarbon)
(iii) Umbilical cord
(iv) Homologous chromosomes
(v) Carboxy-hemoglobin

(b) Correct and rewrite the statements by changing the biological term that is underlined for each statement: [5]
(i) The theory of Inheritance of Acquired Characters was proposed by Watson and Crick.
(ii) The protective sac which develops around the developing embryo is called the Pericardium.
(iii) Maintaining balance of the body and coordinating muscular activities is carried out by the cerebrum.
(iv) The kidney is composed of number of neurons.
(v) The part of the eye which can be donated from a clinically dead person is the Retina.
Answer:
(i) The theory of inheritance of acquired character was proposed by Jean Baptist de Lamarck.
(ii) The protective sac which develops around developing embryo is called Amniotic sac.
(iii) Maintaining balance of body and coordinating muscular activities is carried out by cerebellum.
(iv) The kidney is composed of number of nephrons.
(v) The part of eye which can be donated from clinically dead person is cornea.

(c) Give suitable biological reasons for the following statements: [5]
(i) The birth rate in India is very high.
(ii) Carbon monoxide is dangerous when inhaled.
(iii) Root hairs become flaccid and droop when excess fertilizers are added to the moist soil around them.
(iv) Acid rain is harmful to the environment.
(v) All life on Earth is supported by Photosynthesis.
Answer:
(i) The birth rate in India is very high due to problems like illiteracy and desire for male child.
(ii) Carbon monoxide when inhaled react with haemoglobin and form a stable comound carboxy-hemoglobin due to which deficiency of oxygen takes place.

(iii) When excess fertilizers are added to moist soil around then root hairs become flaccid as concentration of fertilizers in soil become greater and water from root hairs come out of it and become flaccid.

(iv) Acid rain is harmful to the environment as it contains many impurities and causes damage to the monuments like Taj Mahal.

(v) Photosynthesis is performed by plants by converting the light energy into their food to yield certain essential processes. And release of oxygen is one of the products of photosynthesis in plants which is the gas inhaled by all the living species on earth for respiration. Therefore all life is supported by photosynthesis.

(d) Match the items given in Column A with the most appropriate ones in Column B and REWRITE the correct matching pairs: [5]

Answer:
Cranial nerves – 12 pairs
Leydig cells – Testosterone
Acetylcholine – Neurotransmitter
Spinal nerve – 31 pairs
Sneezing – Natural reflex

(e) Choose the correct answer from the four options given below: [5]
(i) While recording the pulse rate, where exactly does a doctor press on our wrist?
(A) Nerve
(B) Vein
(C) Artery
(D) Capillary
Answer:
(C) Artery

(ii) In a human male, a sperm will contain:
(A) Both X and Y chromosomes
(B) Only Y chromosome
(C) Only X chromosome A muscular
(D) Either X or Y chromosome
Answer:
(D) Either X or Y chromosome

(iii) A muscular wall is absent in:
(A) Capillary
(B) Venule
(C) Arteriole
(D) Vein
Answer:
(A) Capillary

(iv) On which day of the menstrual cycle does ovulation take place?
(A) 5^th day
(B) 28^th day
(C) 14^th day
(D) 1^th day
Answer:
(C) 14^th day

(v) Which one of the following does not affect the rate of transpiration?
(A) Light
(B) Humidity
(C) Wind
(D) Age of the plant
Answer:
(D) Age of the plant

(f) Identify the ODD term in each set and name the CATEGORY to which the remaining three belong: [5]
Example : glucose, starch, cellulose, calcium
Odd term : calcium
Category: others are different types of carbohydrates.
(i) Addison’s disease, Cushing’s Syndrome, Acromegaly, Leukemia.
(ii) Insulin, Adrenaline, Pepsin, Thyroxine.
(iii) Axon, Dendron, Photon, Cyton.
(iv) Chicken pox, Colour blindness, Haemophilia, Albinism.
(v) Polythene bag, Crop residue, Animal waste, Decaying vegetable.
Answer:
(i) Lukemia
Category – All other are diseases due to pituitary gland.

(ii) Pepsin
Cateogy – Other are hormones of endocrine glands.

(iii) Photon
Category – Other are parts of Neutron.

(iii) Chicken pox
Category – Other are diseases related to genes.

(iv) Polythene bag
Category – Others are biodegradable wastes.

(g) Expand the following biological abbreviations : [5]
(i) ABA
(ii) IAA
(iii) ATP
(iv) DNA
(v) TSH
Answer:
(i) ABA → AbscisicAcid
(ii) IAA → Indole 3 Acetic Acid
(iii) ATP→ Adenosine triphosphate
(iv) DNA → Deoxyribose nucleic acid
(v) TSH → Thyroid stimulating hormone

(h) Study the picture given below and answer the following questions: [5]

(i) Identity the type of pollution.
(ii) Name one pollutant that causes the above pollution.
(iii) Mention the impact of this pollution on human health.
(iv) State one measure to control this pollution.
(v) What is a ‘Pollutant’? Explain the term.
Answer:
(i) Water pollution
(ii) Industrial waste
(iii) It can cause water diseases like cholera, Diarrhoea
(iv) We should not throw waste in water
(v) Pollutant is any undesirable thing or matter which causes pollution.

Section – II (40 Marks)
Attempt any four questions from this Section.

Question 2.
(a) Given below is an experimental setup to demonstrate a particular tropic movement in germinating seeds. Study the diagram and answer the questions that follow: [5]

(i) Label the parts 1 and 2.
(ii) Name the tropic movement shown by part 1.
(iii) Part 1 is affected by two stimuli. Name them. Which one of the two is stronger?
(iv) What is Thigmotropism? Give one example.
(v) What is meant by ‘Positive’ and ‘Negative’ tropic movements in plants?
Answer:
(i)

1. Radicals
2. Plumule

(ii) Hydrotropism
(iii) Geotropism and hydrotropism are two stimuli and geotropism is stronger.

(iv) The growth movement of plants in response to touch stimulus is called thigmotropism for e.g. cuscutta and vinus have tendrils which coil around other plants in response to one sided contact or touch.

(v) Positive tropic movements in piants means a movement of plant which is in same direction as direction of stimulus.

(b) Mention the exact location of the following: [5]
(i) Testis
(ii) Incus
(iii) Thylakoids
(iv) Amniotic fluid
(v) Corpus cal losum
Answer :
(i) Testis → In scrotum.
(ii) Incus → Between malleus and stapes in middle ear.
(iii) Thylakoids → In chloroplast arranged in piles.
(iv) Amniotic fluid → In Amniotic sac or Amnion
(v) Corpus callosum → between two cerebral hemispheres

Question 3.
(a) The diagram given below represents an experiment to prove the importance of a factor in photosynthesis. Answer the questions that follow: [5]

(i) Name the factor studied in this experiment.
(ii) What will you observe in the experimental leaf after the starch test?
(iii) Explain the process of Photosynthesis.
(iv) Give balanced chemical equation to represent the process of photosynthesis.
(v) Draw a neat, labelled diagram of an experimental setup to show that oxygen is released during photosynthesis.
Answer:
(i) To show that sunlight is necessary for photosynthesis.

(ii) When we put iodine solution to test starch presence on leaf we observed that the part of leaf covered by black paper will turn brown and other part of leaf will turn blue black.

(iii) Photosynthesis is a process of green plants which are able to make food from carbon dioxide and water in presence of chlorophyll and light energy this process by which food is made is called photosynthesis.

(iv) 6CO₂ + 12H₂O C₆H₁₂O₆ + 6O₂ + 6H₂O

(v)

Ail experimental setup to show that oxygen is released (luring photosynthesis.

(b) State the main functions of the following: [5]
(i) Medulla Oblongata
(ii) Cytokinins
(iii) Tears
(iv) Coronary Artery
(v) Seminal Vesicles
Answer:
(i) Medulla oblongata → controls muscular activities.
(ii) Cytokinins → for cell division and growth and development.
(iii) Tears → kills germs and lubricate eyes.
(iv) Coronary artery → supply blood to heart muscles.
(v) Seminal vesicles → helps in making semen which provide nourishment to sperm.

Question 4.
(a) The diagram given below represents an organ system in the human body. Study the same and answer the questions that follow; [5]

(i) Identify the system.
(ii) Label the parts marked 2 and 4. Mention the function of part 5.
(iii) Name the structural and functional units of the part marked 1.
(iv) What is the fluid that accumulates in part 3?
Which is the main nitrogenous waste present in it?
(v) Draw a neat, labelled diagram showing the longitudinal section of part 1.
Answer:
(i) Urinary or excretory system

(ii) 2-ureter 4-sphincter
function of part 5 → helps in urination

(iii) Nephron

(iv) Urine – fluid
Urea → nitrogenous waste

(v)

(b) The diagram given below represents an endocrine gland in the human body. Study the diagram and answer the following questions : [5]

(i) Identify the endocrine gland. Where is it located?
(ii) Why is the above gland referred to as the ‘Master gland’?
(iii) Name the hormone which in deficiency causes Diabetes Insipidus. How does this disorder differ from Diabetes Mellitus?
(iv) Explain the term‘Hormone’.
What is the role of Tropic hormones in the human body?
(v) Which lobe of the above gland secretes :

1. Oxytocin
2. ACTH
3. Growth hormone

Answer:
(i) Pituitary gland
Location → base of mid-brain below hypothalamus.

(ii) As it seems to control practically all other endocrine glands so it is called master gland.

(iiii) Vasopressin
Diabetes mellitus is caused due to insufficient secretion of insulin and diabetis insipidus is called due to insufficient secretion of vasopression.

(iv) Hormones is secreation from gland to co-ordinate body functions.
Tropic hormoness which stimulate other endocrine glands to produce their specific hormones.

(v) Oxytocin → posterior pituitary
ACTH → Anterior pituitary
Growth hormone → Anterior pituitary

Question 5.
(a) Given below is an apparatus which was setup to investigate a physiological process in plants. The setup was placed in bright sunlight. Answer the questions that follow : [5]

(i) Name the process being studied. Define the process.
(ii) Why was the pot enclosed in a rubber sheet?
(iii) Mention two external factors which can accelerate the above process.
(iv) List two adaptations in plants to reduce the above process.
(v) Draw a neat, labelled diagram of a stomatal apparatus.
Answer:
(i) Transpiration
Transpiration means loss of water in form of vapours from plants.

(ii) Rubber sheet will prevent escape of water vapour from pot.
(iii) (I) sunlight (II) temperature (HI) velocity of wind
(iv) (I) sunken stomata (II) Narrow leaves (III) Loss of leaves
(v)

(b) Given below are two stages in the evolution of man. Study them and answer the questions that follow: [5]

(i) Identify Australopithecus and Neanderthal man from the above pictures.
(ii) Mention two characteristic features each for the two stages.
(iii) Who proposed the theory of ‘Natural Selection’?
(iv) Name the organism used as an example to explain ‘Industrial Melanism’.
(v) Give two examples of Vestigial organs in humans.
Answer:
(i) B-Australopithicus
A-Neanderthal man

(ii) Australopithecus

1. Teeth were strikingly mankind because of dental arch was a smoothy rounded parabola.
2. They were small statured.

Neanderthal man

1. They have large head and prominent brow ridges.
2. They have height of about 160 cm.

(iii) Charles Darwin
(iv) Peppered Moth, Biston Betularia
(v)

1. Wisdom teeth
2. Pinna
3. Vermiform Appendix

Question 6.
(a) In Mendel’s experiments, tall pea plants (T) are dominant over dwarf pea ‘plants (t). [5]
(i) What is the phenotype and genotype of the Fj generation if a homozygous tall • plant is crossed with a homozygous dwarf plant?
(ii) Draw a Punnett square board to show the gametes and offspring when both the parents are heterozygous for tallness.
(iii) What is the phenotypic ratio and genotypic ratio of the above cross in (ii)?
(iv) State Mendel’s Law of Dominance.
(v) What is a Dihybrid Cross?
Answer:
(i)

All are heterozygous tall plant.

(ii)

(iii) phenotypic → 3 : 1
genotypic → 1 : 2 : 1

(iv) Law of dominance → Out of a pair of contrasting chromosomes present together only one is able to express itself while other is suppressed and which express itself is dominant and other is recessive.

(v) Dihybrid cross means cross in which 2 characters of plant are given.

(b) Given below is a diagram representing a stage during the mitotic cell division. [5]
Study the diagram and answer the following questions:

(i) Identify the stage by giving a suitable reason.
(ii) Is it a plant or an animal cell? Give a reason to support your answer.
(iii) Draw a neat, labelled diagram of the stage which follows the one shown in the diagram.
(iv) How many chromosomes will each daughter cell have after the completion of the above division?
(v) Name the four nitrogenous bases.
Answer:
(i) Early anaphase
(ii) Animal cell as no cell wall is present
(iii) Late anaphase

(iv) 46 chromosomes
(v) Adenine Cytosine Guanine Thyamine

Question 7.
(a) Answer the following questions briefly: [5]
(i) How are the cytons and axons placed in the brain and the spinal cord?
(ii) Which part of the human ear gives ‘Dynamic balance’ and ‘Static balance’ to the body?
(iii) Explain how the human eye adapts itself to bright light and dim light.
(iv) What is Parthenocarpy? Give one example.
(v) Mention any two objectives of ‘Swachh Bharat Abhiyan’.
Answer:
(i) Brain
Cyton – outside
Axon – inner side
Spinal cord
Cyton – inner side
Axon – outside

(ii) dynamic – semicircular canal static – sacculus
(iii) dim light – pupil dilate bright light – pupil constriet
(iv) Ripening of fruits without germination is process called parthenocarpy. e.g. – bannana

(v) Objectives

1. to clean streets, roads of country’s cities
2. to establish an accountable mechanism of monitoring latrine use.

(b) The diagram given below represents a system in the human body. Study the diagram and answer the following questions: [5]

(i) Identify the system.
(ii) Label the parts marked 5 and 6.
(iii) Name the two hormones secreted by 1.
(iv) Mention the number and the name of the part involved in fertilization and implantation from the above diagram.
(v) Mention the surgical methods of contraception in :

1. Human males.
2. Human females.

Answer:
(i) Female reproductive system

(ii) 5 – oviduct’s funnel
6 – cervix

(iii)

1. oestrogen
2. progesterone

(iv) 2 ovaries fertilization → oviduct
implanatation → uterus

(v)

1. Human males – Vasectomy
2. Human females – Tubectomy

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2012 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2012 Solved

Time: 1 1/2 hour
Maximum Marks: 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper,
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section I and any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section-I (40 Marks)
(Attempt all questions from this section)

Question 1.
(a) Name the following :
(i) The phenomenon by which living or dead plant cells absorb water by surface attraction.
(ii) The phase of cardiac cycle in which the auricles contract.
(iii) The organ where urea is produced.
(iv) The hormone that helps increase the reabsorption of water from the kidney tubules.
(v) Chemical substances produced by micro organisms that can kill or inhibit the growth of other micro organisms. [5]
Answer:
(i) Imbibition
(ii) Systole
(iii) Liver
(iv) Vasopressin (ADH)
(v) Antibiotics

(b) Choose the correct answer from the four options given below each statement :
(i) BCG vaccine is used to build immunity against:
(a) Poliomyelitis
(b) Tuberculosis
(c) Malaria
(d) Whooping cough
Answer:
(b) tuberculosis

(ii) A plant is kept in a dark cupboard for about 48 hours before conducting any experiment on photosynthesis to :
(a) Remove starch from the plant.
(b) Ensure that starch is not translocated from the leaves.
(c) Remove chlorophyll from the leaf of the plant.
(d) Remove starch from the experimental leaf.
Answer:
(a) Remove starch from the plant

(iii) The part of the human eye where rod cells and cone cells are located is the :
(a) Retina
(b) Cornea
(c) Choroid
(d) Sclera
Answer:
(a) Retina

(iv) A reflex arc in man is best described as movement of stimuli from :
(a) Receptor cell, sensory neuron, relaying neuron, effector muscles.
(b) Receptor cell, efferent nerve, relaying neuron, muscles of the body.
(c) Receptor cell, spinal cord, motor neuron, relaying neuron.
(d) Receptor cell, synapse, motor neuron, relaying neuron.
Answer:
(a) Receptor cell, sensory neuron, relaying neuron, effector muscles.

(v) NADP is expanded as :
(a) Nicotinamide, adenosine dinucleotide phosphate.
(b) Nicotinamide, adenine dinucleotide phosphate
(c) Nicotinamide, adenine dinucleous phosphate
(d) Nicotinamide, adenosine dinucleous phosphate. [5]
Answer:
(b) Nicotinamide, adenine, dinucleotide phosphate

(c) State the main function of the following :
(i) Chordae tendinae
(ii) Lymphocytes
(iii) Seminiferous tubule
(iv) Thylakoids
(v) Beta cells of pancreas
Answer:
(i) Chordae tendinae connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
(ii) Lymphocytes produce antibodies and provide immunity to the body.
(iii) Seminiferous tubule produce sperms (male gametes).
(iv) Thylakoids are the site for light reaction during photosynthesis.
(v) Beta cells of pancreas secrete the hormone insulin.

(d) Give the exact location of:
(i) Lenticels
(ii) Prostate gland
(iii) Thyroid gland
(iv) Centrosome
(v) Mitral valve
Answer:
(i) Lenticels – in the stem of woody plants.
(ii) Prostate gland – a bilobed structure surrounding the urethra close to its origin from the bladder.
(iii) Thyroid gland- a butterfly shaped gland is situated in front of the neck below the larynx.
(iv) Centrosome – situated next to the nucleus.
(v) Mitral valve – situated between left atrium and the left ventricle of the heart.

(e) given below are sets of five terms each. In each case rewrite the terms in logical sequence as directed at the end of each statement. An example has been done for you:
Example :
Cortical cells, root hair, xylem, soil water, endodermis (absorption of water by the plants)
Answer: Soil water, root hair, cortical cells, endodermis, xylem.
(i) Active immunity, antigen, antibody, bacteria, lymphocytes (defence mechanisms of the body).
(ii) Implantation, parturition, ovulation, gestation, fertilisation (stages leading to formation of foetus and birth).
(iii) Oval window, tympanum, cochlea, auditory canal, ear ossicles (path through which a vibration of sound is transferred in the human ear).
(iv) Karyokinesis, S-phase, cytokinesis, G1-phase, G2-phase (cell cycle).
(v) Renal vein, renal artery, afferent arteriole, efferent arteriole, glomerulus (pathway of blood through a glomerulus). [5]
Answer:
(i) Bacteria, lymphocytes, antibody, antigen, active immunity.
(ii) Ovulation, fertilisation, implantation, gestation, parturition.
(iii) Tympanum, ear ossicles, ova\ window, cochlea, auditory canal.
(iv) Karyokinesis, G1 -phase, S-phase, G2-phase, Cytokinesis.
(v) Renal artery, afferent arteriole, glomerulus, efferent arteriole, renal vein.

(f) Study the following diagram carefully and then answer the questions that follow. The diagram is depicting a defect of the human eye :

(i) Identify the defect shown in the diagram.
(ii) Give two possible reasons for the above defect.
(iii) Draw a neat labelled diagram to show how the above defect can be rectified.
Answer:
(i) Long sightedness
(ii)

• To flattering of the lens.
• Shortening of the eyeball.

(iii)

(g) Match the items in Column A with that which is most appropriate in Column B. Rewrite the matching pairs.

Answer:
(1) – (g)
(2) – (e)
(3) – (b)
(4) – (e)
(5) – (d)

(h) Given below are six sets with four terms each. In each set a term is an odd one and cannot be grouped in the same category to which the other three belong. Identify the odd one in each set and name the category to which the remaining three belong. The first has been done for your as an example.

No.	Set	Odd one	Category
e.g.:	Cell wall, large vacuole, plastids, centrosome	centrosome	Parts of plant cell
(i)	Cerebrum, cerebellum, thalamus hypothalamus
(ii)	Ovary, ureter, fallopian tube,
(iii)	Adrenal gland, liver, thyroid gland, pituitary gland
(iv)	Malleus, pinna, incus, stapes
(v)	Haemophilia, colour blindness, albinism, night blindness

Answer:

No. Set	Odd one	Category
e.g.: Cell wall, large vacuole, plastids, centrosome	centrosome	Parts of plant cell
(i) Cerebrum, cerebellum, thalamus hypothalamus	Cerebellum	Part of fore-brain
(ii) Ovary, ureter, fallopian tube,	centrosome	Part of female reproductive system
(iii) Adrenal gland, liver, thyroid gland, pituitary gland	Odd one	Endocrine glands
(iv) Malleus, pinna, incus, stapes	Cerebellum	Middle ear
(y) Haemophilia., colour blindness, albinism, night blindness	Ureter	Hereditary, diseases

Section-II (40 Marks)
(Attempt any four questions from this section)

Question 2.
(a) Given below is an experimental set up to demonstrate a particular process. Study the same and answer the questions that follow.

(i) Name the physiological process being studied.
(ii) Explain the process mentioned above.
(iii) What is the aim of the above experiment ?
(iv) What would you observe in the experimental set-up after an hour ? Give a reason to support your answer.
(v) Mention any three adaptations found in plants to overcome the physiological process mentioned in (i) above. [5]
Answer:
(a) (i) Transpiration in plants.
(ii) Transpiration is the loss of water vapour from the surface of the plant, mainly from the leaves.
(iii) To compare the transpiration on the two sides or surfaces of a dorsiventral leaf.
(iv) After an hour, the paper on the lower surface of the leaf turns pink whereas the paper on the upper surface takes more time to do so. This proves that more transpiration takes place on the lower surface due to the presence of numerous stomata on it.
(v)

• Leaves with thick cuticle
• Sunken stomata
• Leaves modified to spines

(b) Give biological/technical terms for the following :
(i) A membrane which allows the passage of molecules selectively.
(ii) The suppressed allele of a gene.
(iii) Structure that carries visual stimuli from retina to the brain.
(iv) WBCs squeeze through the walls of the capillaries into the tissue.
(v) Protective coverings located round the human brain and spinal cord.
(vi) Eye lens losing flexibility resulting in a kind of long sightedness in elderly people.
(vii) Hormones which stimulate other endocrine glands to produce their specific hormones.
(viii) The phase in the menstrual cycle in which the remnant of follicle in the ovary turns to Corpus luteum.
(ix) Statistical study of human population.
(x) Artificially introducing weekend germs or germ substance into the body for developing resistance to a particular disease. [5]
Answer:
(i) Semi permeable membrane.
(ii) Recessive
(iii) Optic nerve
(iv) Diapedesis
(v) Meninges
(vi) Astigmatism
(vii) Hormones of pituitary gland
(viii) Secretory phase
(ix) Demography
(x) Vaccination

Question 3.
(a) Given below in the diagram of a cell as seen under the microscope after having been placed in a solution:

(i) What is the technical term used for the state/condition of the cell given above?
(ii) Give the technical term for the solution in which the cell was placed.
(iii) Name the parts numbered 1 to 4.
(iv) Is the cell given above a plant cell or an animal cell ? Give two reasons in support of your answer as evident from the diagram.
(v) What would you do to bring this cell back to its original condition? [5]
Answer:
(i) Plasmolysed cell
(ii) Hypertonic solution
(iii)

1. Nucleus
2. Chloroplast
3. Vacuole
4. Cell sap

(iv) It is a plant cell, because

• There are chloroplasts in the cell.
• The shape of a cell is hexagonal i.e., a plant cell.

(v) We can place it in a hypotonic solution.

(b) Differentiate between the following pairs on the basis of what is mentioned in brackets:
(i) Natality and mortality (definition)
(ii) Stoma and Storma (describe its structure)
(iii) Acromegaly and Cretinism (symptoms)
(iv) Transpiration and Guttation (structure involved)
(v) Diabetes mellitus and Diabetes insipidus (reasonlcause) [5]
Answer.
(i) Natality is the number of births per 1000 individuals in the population per year.
Mortality is the number of deaths per 1000 individuals in the population per year.
(ii) Stoma is a pore present in the epidermis of leaves.
Stroma is a fluid in chloroplast containing enzymes that use ATP.
(iii) Acromegaly is a chronic condition developing in adulthood due to over production of growth hormone.
Cretinism is a condition that results from inadequate secretion of thyroid hormones during fetal life.
(iv) Transpiration takes place through stomata while guttation takes place though hydathodes.
(v) Diabetes mellitus s caused due to insufficient secretion of insulin. Diabetes insipidus is caused due to the excess secretion of insulin.

Question 4.
(a) The diagram below shows the Exretory System of a Human being. Study the same and then añswer the questions that follow:

(i) Name the parts labelled 1, 2, 3 and 4.
(ii) Give the main function of the parts labelled 5, 6, 7 and 8.
(iii) Name the endocrine gland which could be added in the diagram and state its location/position. 15]
Answer:
(i)

1. Posterior Vena cava
2. Aorta
3. Left renal artery
4. Left renal vein

(ii) 5. Ureters convey the urine from the kidneys to the bladder.
6. Urinary bladder is large sac in which urine is stored or collected.
7. Sphincter controls the release of urine from the bladder.
8. Urethra let the urine drain from the bladder.

(iii) Adrenal gland, it is located at the top of each kidney.

(b) Briefly explain the following:
(i) Osmosis
(ii) Allele
(iii) Pulse
(iv) Reflex action
(v) Synapse [5]
Answer.
(i) Osmosis is the net movement of water molecules from a region of their higher concentration to a region of their higher concentration through a semipermeable membrane.
(ii) A pair of genes that controls the two alternative expressions of the same character and has the same loci in the homologous chromosomes is called the allele.
(iii) The rhythmic contraction of the heart felt in certain areas like the wrist in the form of pulsations, and this is called pulse.
(iv) Reflex actions are involuntary actions controlled by the spinal cord. It is a rapid automatic response to a stimulus.
(v) Synapse is a junctional region between two neurons where information from one neuron is transmitted or relayed (handed over) to another neuron, but there is no protoplasmic connection between the two neurons.

Question 5.
(a) Study the diagram given below and then answer the question that follow:

(i) Name the part labelled A. Name any two hormones produced by the part labelled A.
(ii) What happens to the part labelled B
(1) If fertilisation takes place?
(2) If fertilisation does not take place?
(iii) Where does fertilisation occur?
(iv) Draw a neat diagram of the human sperm as seen under high magnification and label the following parts.
(1) Acrosome
(2) Mitoehondria
Answer:
(i) Ovary
Ovary pruces the hormones Estrogen and Progestrone.
(ii) (1) Endomentrium secretes nutrients in preparation for implantation.
(2) If fertilisation does not take place, it degenerates or shed from the body.
(iii) Fertilisation takes place in the ampulla of the fallopian tube.
(iv)

(b) A homozygous plant having round (R) and yellow (Y) seed is crossed with homozygous plant having wrinkled (r) and green (y) seeds:
(i) Give the scientific name of the plant on which Mendel conducted his hybridization experiments.
(ii) Give the genotype of the F1 generation.
(iii) Give the dihybrici phenotypic ratio and the phenotype of the offspring of F2 generation
when two plants of the F1 generation are crossed.
(iv) Name and state the law which explains the dihybrid ratio.
(v) Give the possible combinations of gametes that can be obtained from F₁ hybrid. [5]
Answer:
(i) Pisum sativum
(ii) Tt (Heterozygous)
(iii) Dihybrid phenotypic ratio = 9 : 3 : 3 : 1
Phenotype of F₂ generation =
9 round and yellow
3 round and green
3 wrinkled and yellow
1 wrinkled and green
(iv) Law of independent assortment: When more than one pair of contrasting characters are brought together in an individual, the entry of one pair of allele (controlling one character) separates independently and assorts independently of any other pair of alleles (controlling another character).
(v) F₁ Hybrid = Tt
possible combinations of gamets = T, t

Question 6.
(a) The diagram given below is an experiment conducted to study a factor necessary for Photosynthesis. Observe the diagrams and then answer the following questions :

(i) What is the aim of the experiment ?
(ii) Name the test performed on the leaf and the solution used for test.
(iii) What type of leaf was used for the experiment ? Give an example.
(iv) What is the expected result of the above test on the parts labelled A and B ?
(v) Give a balanced chemical to represent the process of Photosynthesis. [5]
Answer:
(i) To demonstrate that chlorophyll is essential for photosynthesis.
(ii) Starch test, iodine is used for this test.
(iii) Variegated leaf, for example coleus.
(iv) Part A will remain unchanged.
Part B will turn blue-black in colour.
(v)

(b) The diagrams given below show the cross section of two kinds of blood vessels :

(i) Identify the blood vessels A and B. In each case give a reason to support your answer.
(ii) Name the parts numbered 1 and 2.
(iii) When are the sounds “LUBB” and “DUP” produced during a heartbeat ?
(iv) Name the blood vessel that
(1) begins and ends in capillaries.
(2) supplies blood to the walls of the heart.
Answer.
(i) ‘A’ is a artery while ‘B’ is a vein.
The size of lumen in A is small, so it is an artery.
The size of lumen in B is larger, so it is a vein.
(ii) 1-Endothelium (Tunica Interna). 2-Lumen of the vessel
(iii) The sound ‘LUBB’ occurs due to the closure of the atrioventricular valves. While ‘DUP’ sound occurs as the aortic and pulmonary valves close to prevent the back flow of the blood.
(iv)
(1) Hepatic portal vein
(2) Coronary arteries

Question 7.
(a) Answer the following :
(i) Draw a well labelled diagram of a ‘Neuron’ and name the following parts :
(1) Node of Ranvier
(2) Nissil granules
(3) Cyton
(ii) Name the part of the human brain which is concerned with the following :
(1) Seat of memory
(2) Coordinates muscular activity
(iii) Mention any three major activities of the WHO.
Answer:
(i)

(ii)
(1) Cerebrum
(2) Cerebellum
(iii) WHO

• Promotes medical education and training.
• Promotes research and development of international standard for pharmaceutical products.
• To lay pharmaceutical standards for important drugs, ensure purity and size of the dose.

(b) (i) Draw a well labelled diagram to show the metaphase state of Mitosis in an animal cell having four chromosomes.
(ii) Mention any two reasons for the population explosion in INDIA.
(iii) Give biological reasons for the following :
(1) Pituitary gland is also known as the master gland.
(2) Gametes have a haploid number of chromosomes.
Answer:
(i) Metaphase plate

(ii)

• Desire to have a male child.
• Lack of education

(iii) (1) Pituitary gland influences almost all the endocrine glands of the body, so it is also called the master gland.
(2) Gametes contain half the normal number of chromosomes.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2021 Semester 1 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2021 Solved Semester 1

Time : 1\(\frac{1}{2}\) hour
Maximum Marks : 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 10 minutes.
• This time is to be spent in reading the question paper.
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section A and any any three questions from Section B.
• The marks intended for questions are given in brackets [ ].

Section – A
(Attempt all questions from this Section)

Question 1.
Name the following by choosing the correct option: [10]
(i) The process of conversion of ADP to ATP during photosynthesis:
(a) Polymerisation
(b) Photophosphorylation
(c) Photorespiration
(d) Photolysis
Answer:
(b) Photophosphorylation

(ii) Permanently open structures seen on the barks of old woody stems:
(a) Stomata
(b) Hydathodes
(c) Lenticels
(d) Epidermal pores
Answer:
(c) Lenticels

(iii) The pressure developed in the roots due to continuous inward movement of water by cell to cell osmosis:
(a) Root Pressure
(b) Wall Pressure
(c) Turgor Pressure
(d) Air Pressure
Answer:
(a) Root pressure

(iv) The type of gene, which in presence of a contrasting allele is not expressed:
(a) Homozygous
(b) Heterozygous
(c) Dominant
(d) Recessive
Answer:
(d) Recessive

(v) After mitosis, a female human cell will have:
(a) 44 + XX chromosomes
(b) 22 + X chromosomes
(c) 22 + Y chromosomes
(d) 44 + XY chromosomes
Answer:
(d) 44 + XX chromosomes

Question 2.
Complete the following statements by chocsing the appropriate option for each blank:
(i) At the end of ____________ cytokinesis is completed.
(a) Metaphase
(b) Prophase
(c) Interphase
(d) Telophase
Answer:
(d) Telophase

(ii) The genotype of a person who cannot roll his tongue is _____________.
(a) Rr
(b) RR
(c) rr
(d) RRr
Answer:
(c) rr

(iii) When a cell is placed in a ____________ solution it becomes plasmolysed.
(a) Distilled water
(b) Hypertonic
(c) Isotonic
(d) Hypotonic
Answer:
(b) Hypertonic

(iv) The nitrogenous base Adenine always pairs with ____________
(a) Thymine
(b) Guanine
(c) Cytosine
(d) Thiamine
Answer:
(a) Thymine

(v) The basic units of heredity are ____________
(a) Chromosomes
(b) Chromatids
(c) Genes
(d) Centrosome
Answer:
(c) Genes

Question 3.
Choose the correct answer from each of the four options given below:
(i) NADP is expanded as:
(a) Nicotinamide Adenosine Dinucleotide Phosphate
(b) Nicotinamide Adenine Dinucleotide Phosphate
(c) Nicotinamide Adenine Dinucleolus Phosphate
(d) Nicotinamide Adenosine Dinucleolus Phosphate
Answer:
(b) Nicotinamide Adenine Dinucleotide Phosphate

(ii) Transpiration is useful to the plant because it:
(a) Creates a suction force for absorption of water from the soil
(b) Helps in photophosphorylation
(c) Synthesises glucose
(d) Splits water molecules
Answer:
(a) Creates a suction force for absorption of water from the soil

(iii) A homozygous pea plant having purple flowers is crossed with a homozygous pea plant bearing white flowers. The phenotypic ratio of the offspring obtained in F₂ generation is:
(a) 2 : 1
(b) 1 : 1
(c) 1 : 2 : 1
(d) 3 : 1
Answer:
(d) 3 : 1

(iv) The shoot from a balsam plant is kept in a beaker containing eosin solution (pink). The pink colour will be distinctly seen in the:
(a) Xylem
(b) Phloem
(c) Epidermis
(d) Cortex
Answer:
(a) Xylem

(v) Replication of DNA in the cell cycle occurs during the:
(a) G₁ – Phase
(b) Anaphase
(c) S – Phase
(d) G₂ – Phase
Answer:
(c) S – Phase

Question 4.
Explain the following terms:
(i) Karyokinesis
(a) It is the division of nucleus during cell division
(b) It is the division of cytoplasm during cell division
(c) It is the division of centrosome
(d) It is the division of nucleolus
Answer:
(a) It is the division of nucleus during cell division.

(ii) Law of Dominance
(a) Out of a pair of contrasting alleles present together, only the recessive allele is able to express itself while the dominant remains suppressed
(b) Out of a pair of contrasting alleles present together, only the dominant allele is able to express itself while the recessive remains suppressed
(c) Out of a pair of contrasting alleles present together, both dominant and recessive cannot express themselves
(d) Out of a pair of contrasting alleles present together, both dominant and recessive can express themselves
Answer:
(b) Out of a pair of contrasting alleles present together, only the dominant allele is able to express itself while the recessive remains supressed.

(iii) Mutation:
(a) It is a sudden change in one or more genes in an organism’s cells which is heritable
(b) It is a change in the number of centrosomes in an organism’s cell which is heritable
(c) It is a change in the structure of cell membrane in an organism’s cells which is heritable
(d) It is a change in the shape of cells which is heritable
Answer:
(a) It is a sudden change in one or more genes in an organism’s cells which is heritable.

(iv) Photosynthesis
(a) It is the synthesis of glucose from carbon dioxide by non-green plants using light energy.
(b) It is the synthesis of glucose by green plants from carbon dioxide using light energy.
(c) It is the synthesis of glucose from carbon dioxide and water by non-green plants using light energy.
(d) It is the synthesis of glucose from carbon dioxide and water by green plants using light energy.
Answer:
(d) It is the synthesis of glucose from carbon dioxide and water by green plants using light energy.

(v) Transpiration:
(a) It is the loss of water in the form of droplets from the aerial parts of the plant.
(b) It is the loss of water in the form of water vapour from the underground parts of the plant.
(c) It is the loss of water in the form of water vapour from the aerial parts of the plant.
(d) It is the loss of water in the form of water vapour from all parts of the plant.
Answer:
(c) It is the loss of water in the form of water vapour from the aerial parts of the plant.

Question 5.
Mention the exact location of the following:
(i) Aster
(a) Around the centrioles in plant cells
(b) Around the centrioles in animal cells
(c) Around the chromatids in animal cells
(d) Around the chromatids in plant cells
Answer:
(b) Around the centrioles in animal cells

(ii) Guard cells
(a) Around the root hairs
(b) Around the lenticels
(c) Around the thylakoids
(d) Around the stoma
Answer:
(d) Around the stoma

(iii) Xylem tissue:
(a) Conducts water and minerals in leaves
(b) Does uot conduct water and minerals in stems
(c) Conducts food and nutrition to roots
(d) Conducts food and nutrients to all parts of the plant
Answer:
(a) Conducts water and minerals in leaves

(iv) Centrioles
(a) Found only in plant cells
(b) Found inside nucleus
(c) Found only in animal cells
(d) Found in animals and plant cells
Answer:
(c) Found only in animal cells

(v) Genes
(a) Present on cell walls
(b) Present on chloroplast
(c) Present on chromosomes
(d) Present on centrosomes
Answer:
(c) Present on chromosomes

Question 6.
State the function of the following:
(i) Cell wall
(a) Regulates entry of solutes in plant cells
(b) Regulates entry of solutes in animal cells
(c) Gives rigidity and shape to plant cells
(d) Gives rigidity and shape to animal cells
Answer:
(c) Gives rigidity and shape to plant cells.

(ii) Centromere:
(a) It is the point of attachment of two sister chromatids
(b) It is the point of attachment of two centrioles
(c) It is the point of attachment of two centrosomes
(d) It is the point of attachment between two daughter nuclei
Answer:
(a) It is the point of attachment of two sister chromatids.

(iii) Cuticle on leaves:
(a) Prevents photosynthesis
(b) Reduces transpiration
(c) Protects leaves from grazing animals
(d) Gives colour to leaves
Answer:
(b) Reduces transpiration.

(iv) Hydathodes
(a) Transpiration
(b) Absorption of water
(c) Photosynthesis
(d) Guttation
Answer:
(d) Guttation.

(v) Grana of chloroplast is not the:
(a) Site of Light Independent Phase
(b) Site of Light Dependent Phase
(c) Site of Photolysis
(d) Site of Photon Absorption
Answer:
(a) Site of Light Independent phase.

Question 7.
The diagram given below presents an experiment to demonstrate a particular aspect of Photosynthesis. The letter ‘A’ indicates a certain condition inside the flask:
Answer the Questions:

(i) What is the aim of the experiment?
(a) To show that oxygen is released during photosynthesis
(b) To show that photosynthesis occurs in the presence of KOH
(c) To show that chlorophyll is necessary for photosynthesis
(d) To show that carbon dioxide is necessary for photosynthesis
Answer:
(d) To show that carbon dioxide is necessary for photosynthesis.

(ii) What is the special condition inside the flask?
(a) Air inside the flask is free of oxygen
(b) Air inside the flask is free of carbon dioxide
(c) Air inside the flask is free of nitrogen
(d) KOH purifies the air inside the flask
Answer:
(b) Air inside the flask is free of carbon dioxide.

(iii) An alternative chemical that can be used instead of KOH is:
(a) Sodium Hydroxide
(b) Sodium Chloride
(c) Potassium Chloride
(d) Potassium Permanganate
Answer:
(a) Sodium Hydroxide.

(iv) In what manner, do the leaves 1 and 2 differ at the end of the starch test?
(a) Leaf 1 turns brown, Leaf 2 turns blue black
(b) Leaf 1 turns blue black, Leaf 2 turns blue brown
(c) Leaf 1 turns purple, Leaf 2 remains green
(d) There is no change in the colour of the leaves
Answer:
(a) Leaf 1 turns brown, Leaf 2 turns blue black.

(v) What is the important step that should be taken before performing this experiment?
(a) The plant should be placed in dark for 24 hours to destarch the entire plant.
(b) The plant should be placed in dark for 24 hours to remove chlorophyll from the leaves
(c) The plant should be placed in dark for 24 hours to destarch the leaves
(d) The plant should be placed in dark for 24 hours for the roots to absorb water
Answer:
(c) The plant should be placed in dark for 24 hours to destarch the leaves.

Question 8.
Given below is the diagram of an experiment step-up to study the process of Transpiration. Cobalt chloride papers are fixed on the upper as well as lower surface of the leaf.

Answer the question that follow:
(i) What is the aim of the experiment?
(а) To prove that more transpiration occurs from the lower surface of a dicot leaf
(b) To prove that more transpiration occurs from the upper surface of a dicot leaf
(c) To prove that transpiration is equal on both sides of the leaf
(d) To prove that transpiration does not take place in a dicot leaf
Answer:
(a) To prove that more transpiration occurs from the lower surface of a dicot leaf.

(ii) What is the colour of dry Cobalt Chloride paper?
(a) Pink
(b) Blue
(c) Brown
(d) White
Answer:
(b) Blue

(iii) After about an hour, what change, if any, would you expect to find in the cobalt chloride paper placed on the upper and lower surface of the leaf?
(a) Upper Surface – Pink, Lower Surface – Blue
(b) Upper Surface – White, Lower Surface – Blue
(c) Upper Surface – less Pink, Lower Surface – more Pink
(d) Upper Surface – more Pink, Lower Surface – less Pink
Answer:
(c) Upper surface – less pink, lower surface – more pink

(iv) Two adaptation in plants to reduce transpiration are:
(a) Narrow Leaves, Thin cuticles
(b) Fewer Stomata, Broad lamina of leaves
(c) Thin cuticles, Sunken stomata
(d) Narrow leaves, Fewer stomata
Answer:
(d) Narrow leaves, Fewer stomata

(v) The rate of transpiration is less when there is:
(a) High humidity in the air and low temperature
(b) Less humidity in the air and decrease in atmospheric pressure
(c) Bright sunlight and high temperature
(d) More wind and low intensity of sunlight
Answer:
(a) High humidity in the air and low temperature.

Solving ICSE Class 10 Biology Previous Year Question Papers ICSE Class 10 Biology Question Paper 2022 Semester 2 is the best way to boost your preparation for the board exams.

ICSE Class 10 Biology Question Paper 2022 Solved Semester 2

Time: 1 1/2 hour
Maximum Marks: 40

General Instructions :

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 10 minutes.
• This time is to be spent in reading the question paper.
• The time given at the head of this Paper is the time allowed for writing the answers.
• Attempt all questions from Section A and any any three questions from Section B.
• The marks intended for questions are given in brackets [ ].

Section – A
(Attempt all questions from this Section)

Question 1.
Choose the correct answers to the questions from the given options. (Do not copy the question. Write the correct answer only.)   [10]
(i) The mineral element in haemoglobin :
(a) Manganese
(b) Iron
(c) Sodium
(d) Calcium
Answer:
(b) Iron

(ii) The number of cranial nerves in humans are :
(a) 16 pairs
(b) 31 pairs
(c) 39 pairs
(d) 12 pairs
Answer:
(d) 12 pairs

(iii) Gigantism and Acromegaly are due to :
(a) Hypersecretion of Growth hormones
(b) Hypersecretion of Thyroxine
(c) Hyposecretion of Growth hormone
(d) Hyposecretion of Thyroxine
Answer:
(a) Hypersecretion of Growth hormones

(iv) Pericardium covers the :
(a) Heart
(b) Brain
(c) Spinal cord
(d) Eyeball
Answer:
(a) Heart

(v) The circular opening in the centre of iris :
(a) Lens
(b) Cornea
(c) Sclera
(d) Pupil
Answer:
(d) Pupil

(vi) The blood vessel that carries oxygenated blood is :
(a) Pulmonary artery
(b) Pulmonary vein
(c) Renal vein
(d) Hepatic vein
Answer:
(b) Pulmonary vein

(vii) Organ of corti is present inside the :
(a) Cochlea
(b) Semicircular canals
(c) Sacculus
(d) Utriculus
Answer:
(a) Cochlea

(viii) The structure that stores urine temporarily is :
(a) Ureter
(b) Urethra
(c) Urinary bladder
(d) Kidneys
Answer:
(c) Urinary bladder

(ix) Islets of Langerhans are located in :
(a) Liver
(b) Pituitary gland
(c) Spleen
(d) Pancreas
Answer:
(d) Pancreas

(x) The main nitrogenous waste formed in the human body :
(a) Uric acid
(b) Urea
(c) Ammonia
(d) Creatinine
Answer:
(b) Urea

Section – B
(Attempt any three questions from this Section)

Question 2.
(i) Simple goitre is usually seen in people living in the hilly regions. Give two reasons for the statement. [2]
Answer:
2 reasons for simple goitre is usually seen in people living in hilly region are :
(a) In hilly areas soil has deficiency of iodine.
(b) It is caused by hyposecretion of thyroxine, due to deficiency of iodine.

(ii) What are the two types of blood circulation in humans ? [2]
Answer:
Two circulations in human body are :
(a) Pulmonary Circular (pertains to lungs)
(b) Systemic Circulation (pertains to major circulation in body)

(iii) Mention the three major steps involved in the production of urine. [3]
Answer:
3 major steps involved in production of urine are
(a) Ultrafiltration
(b) Reabsorption
(c) Tubular Secretion

(iv) Draw a neat diagram of a Neuron and label any two parts. |3]
Answer:

Question 3.
(i) What is Adrenal Virilism ? What causes this condition ? [2]
Answer:
When a mature woman develops certain male features, such as, beard, moustaches and deep male voice. This condition is called Adrenal Virilism. This condition is called Adrenal virilism. It is due to overgrowth of adrenal cortex.

(ii) Which is the light sensitive layer of the eyeball ? [2]
Where exactly is the image formed on this layer ?
Answer:
The light sensitive layer of the eyeball is Retina.
Red cell → sensitive to dim light.
Cone cell → sensitive to bright light.
Image is formed on yellow spot (Macule Lutea) on Retina.

(iii) Study the diagram given below and answer the questions that follow: [3]
(a) Identify the defect of the eye by mentioning the technical term.
(b) Mention one reason for this defect.
(c) Name the type of lens used to correct this defect.
Answer:
(a) Hypermetropia or Hyperopia.
(b) Defect reason It is due to shortening of eyeball from front to back or lens is too flat.
(c) It can be correct by using convex lens.

(iv) Give the biological terms for the three tiny bones present in the middle ear. [3]
Answer:
Ear Ossicle is the biological term for the three tiny bones. Tiny bones are :

1. Malleus
2. Incus
3. Stapes

Question 4.
(i) Name the endocrine gland that secretes Thyroxine. [2]
Give any one function of Thyroxine.
Answer:
Thyroxine is secreted by Thyroid gland
Function → It regulates basal metabolism.

(ii) Give the full form of the abbreviation ACTH. [2]
Which gland secretes this hormone ?
Answer:
ACTH → Adrenocorticotropic Hormone
It is secreted by Pituitary gland.

(iii) Define the term Synapse. [3]
How are Cytons and Axons of neutrons placed in the Cerebrum ?
Answer:
Synapse is point of contact between terminal branches of the axon of neuron with dendrites of another neuron ’ separated by a fine gap. Axons are placed in inner portion whereas cytons are placed in outer portion of brain but in spinal cords, axons are placed in outer side and cytons are placed in inner portion.
Cerebrum is part of brain.

(iv) Name the three membraneous coverings of the human brain. [3]
Answer:
3 membraneous coverings of human brain :

1. Dura mater – outennost membrane
2. Arachnoid – middle membrane
3. Pia mater – innermost membrane

Question 5.
(i) Name the nerve that transmits impulses to the brain from : [2]
(a) Ear (b) Eye
Answer:
(a) Ear → Auditory nerve
(b) Eye → Optic nerve

(ii) A mature mammalian erythrocyte lacks nucleus and mitochondria but is efficient in its functioning. Explain by giving suitable reasons. [2]
Answer:
A mature erythrocyte lacks nucleus and mitochondria. So as to make a place for accommodation of more haemoglobin and hence more oxygen molecule. Lack of such organelles also provides percular biconcave appearance of RBC’s that aids in efficient diffusion.

(iii) The diagram given below is that of a human brain. Answer the questions that follow : [3]

(a) Label the parts numbered 2 and 3.
(b) State any one function of the part numbered 1.
Answer:
(a) 2 → Cerebellum
3 → Medulla oblongata
(b) Part 1 is cerebrum and it controls all the voluntary actions, consciousness and will power.

(iv) What is a reflex action ? Name the two types of reflexes. [3]
Answer:
Reflex action is an automatic / quick / immediate involuntary action in body brought about by a stimulus.
Two types of Reflexes are :

1. Natural (inborn) e.g. → blinking, sneezing
2. Conditioned (acquired) e.g. → taste, smell of familiar taste.

Question 6.
(i) Give the exact location of Pulmonary semilunar valve. When does it close ? [2]
Answer:
Pulmonary semilunar valve is located between right ventricle and pulmonary artery and has three cups. It prevents back flow of blood into right ventricle.

(ii) Name the hormones whose deficiency causes: [2]
(a) Diabetes mellitus
(b) Diabetes insipidus
Answer:
(a) Diabetes mellitus → Insulin
(b) Diabetes insipidus → ADR (Antidiuretic Hormone)

(iii) Draw a neat diagram of a longitudinal section of a human kidney and label Renal Cortex and Renal Medulla on the diagram. |3]
Answer:

(iv) Mention one function for each of the following: [3]
(a) Lymphocytes
(b) Thrombocytes
(c) Neutrophils
Answer:
(a) Lymphocytes → produce anti-bodies
(b) Thrombocytes → helps in blood clotting
(c) Neutrophils → engulfs and destroys bacteria

Solving ICSE Class 10 Chemistry Previous Year Question Papers ICSE Class 10 Chemistry Question Paper 2020 is the best way to boost your preparation for the board exams.

ICSE Class 10 Chemistry Question Paper 2019 Solved

Time: 2 hours
Maximum Marks: 80

General Instructions:

• Answers to this Paper must be written on the paper provided separately.
• You will not be allowed to write during the first 15 minutes.
• This time is to be spent in reading the Question Paper.
• The time given at the head of this paper is the time allowed for writing the answers.
• Section I is compulsory. Attempt any four questions from Section II.
• The intended marks for questions or parts of questions are given in brackets [ ].

Section – I (40 MARKS)
(Attempt all questions from this Section)

Question 1.
(a) Choose the correct answer from the options given below: [5]
(i) The element with highest ionization potential, is :
(A) Hydrogen
(B) Caesium
(C) Radon
(D) Helium
Answer:
(D) Helium

(ii) The inert electrode used in the electrolysis of acidified water, is :
(A) Nickel
(B) Platinum
(C) Copper
(D) Silver
Answer:
(B) Platinum

(iii) A compound with low boiling point, is :
(A) Sodium chloride
(B) Calcium chloride
(C) Potassium chloride
(D) Carbon tetrachloride
Answer:
(D) Carbon tetrachloride

(iv) The acid which can produce carbon from cane sugar, is :
(A) Concentrated Hydrochloric acid
(B) Concentrated Nitric acid
(C) Concentrated Sulphuric acid
(D) Concentrated Acetic acid
Answer:
(C) Concentrated Sulphuric acid

(v) The organic compound having a triple carbon-carbon covalent bond, is:
(A) C₃H₄
(B) C₃H₆
(C) C₃H₈
(D) C₃H₁₀
Answer:
(A) C₃H₄

(b) State one relevant observation for each of the following reactions: [5]
(i) Action of concentrated nitric acid on copper.
(ii) Addition of excess ammonium hydroxide into copper sulphate solution.
(iii) A piece of sodium metal is put into ethanol at room temperature.
(iv) Zinc carbonate is heated strongly.
(v) Sulphide ore is added to a tank containing oil and water, and then stirred or agitated with air.
Answer:
(i) CU + 4HNO₃ → CU(NO₃)₂ (Blue colour) + 2H₂O + 2NO₂↑ (Dark Brown gas)
The solution turns blue with the liberation of a dark brown gas.

(ii) CuSO₄ + 2NH₄OH → Cu(OH)₂ + (NH₄)₂SO₄
CU(OH)₂ + (NH₄)₂SO₄ + 2NH₄OH →
[CU(NH₃)₄]SO₄ (Blue colouration) + 4H₂O
When excess ammonium hydroxide is added to copper sulphate solution, pale blue precipitates appear which dissolve in excess of ammonium hydroxide forming blue colouration.

(iii) 2C₂H₅OH + 2Na → C₂H₅ONa + H₂↑
Brisk effervescence due to liberation of hydrogen gas are observed.

(iv)

When zinc carbonate is heated a residue is formed which is yellow when hot and white when cold.

(v) When sulphide ore is added to a tank containing oil and water, and then stirred or agitated with air.
The sulphide ore dissolves in the froth and get separated.

(c) Write a balanced chemical equation for each of the following: [5]
(i) Reaction of carbon powder and concentrated nitric acid.
Answer:
C + 4HNO₃ → CO₂ + 2H₂O + 4NO₂

(ii) Reaction of excess ammonia with chlorine.
Answer:
8NH₃ (Excess) + 3Cl₂ → N₂ + 6NH₄Cl

(iii) Reaction of lead nitrate solution with ammonium hydroxide.
Answer:
Pb(NO₃)₂ + 2NH₄OH → Pb(OH)₂ + 2NH₄NO₃

(iv) Producing ethane from bromo ethane using Zn/Cu couple in alcohol.
Answer:

(v) Complete combustion of ethane.
Answer:
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O

(d) (i) Draw the structural formula for each of the following: [5]
1. 2,2 dimethyl pentane
2. methanol
3. Iso propane
Answer:

(ii) Write the IUPA C name of the following compounds :
1. acetaldehyde
2. acetylene
Answer:
1. CH₃CHO acetaldehyde → Ethanal
2. C₂H₂ acetylene Ethyne

(e) State one relevant reason for each of the following: [5]
(i) Graphite anode is preferred to platinum in the electrolysis of molten lead bromide
Answer:
Platinum anode reacts with bromine vapours to form platinum bromide.

(ii) Soda lime is preferred to sodium hydroxide in the laboratory preparation of methane.
Answer:
Soda lime is a mixture of sodium hydroxide and calcium oxide. This sodium hydroxide brings about the reaction and calcium oxide removes the water, thus preventing the reversible reaction.

(iii) Hydrated copper sulphate crystals turn white on heating.
Answer:

Hydrated copper sulphate loses its five molecules of water and turns anhydrous. This anhydrous copper sulphate is white in colour.

(iv) Concentrated nitric acid appears yellow, when it is left for a while in a glass bottle.
Answer:
4HNO₃ → 2H₂O + 4NO₂ + O₂
A part of concentrated nitric acid splits to form water, nitrogen dioxide and oxygen. Nitrogen dioxide formed is brown in colour but when it dissolves in nitric acid it gives yellow colouration to it.

(v) Hydrogen chloride gas fumes in moist air.
Answer:
Hydrogen chloride gas when exposed to air, gives white fumes due to the formation of hydrochloric acid on reacting with atmospheric water vapour.

(f) Calculate: [5]
(i) The amount of each reactant required to produce 750 mL of carbon dioxide, when two volumes of carbon monoxide combine with one volume of oxygen to produce two volumes of carbon dioxide.
2CO + O₂ → 2CO₂
Answer:

1. 2 vol. of CO₂ is formed from 2 vol. of CO.

750 mL of CO₂ is formed from 750 mL of CO.

2. 2 vol. of CO₂ is formed from 1 vol. of O₂.
1 vol. of CO₂ is formed from \(\frac{1}{2}\) vol. of O,.
750 mL of CO₂ is formed from \(\frac{1}{2}\) × 750 mL of
O₂ = 375 mL of O₂

(ii) The volume occupied by 80 g of carbon dioxide at STP.
Answer:
CO₂
Molecular Mass = [12 + 16 × 2] = 44g
44 g of CO₂ occupies 22.4 l

(iii) Calculate the number of molecules in 4.4 gm of COT
[Atomic mass of C = 12, O = 16]
Answer:
44 g of CO₂ contain 6.022 × 10²³ molecules
1 g of CO₂ contain \(\frac{6.022 \times 10^{23}}{44}\) molecules
4.4 g of CO₂ contains \(\frac{6.022 \times 10^{23}}{44}\) × 4.4 g
= 6.022 × 10²² molecules

(iv) State the law associated in question no. (f)(i) above.
Answer:
Gay Lussac’s Law

(g) Give one word or a phrase for the following statements: [5]
(i) The chemical bond formed by a shared pair of electrons, each bonding atom contributing one electron to the pair.
(ii) Electrode used as cathode in electrorefining of impure copper.
(iii) The substance prepared by adding other metals to a base metal in appropriate proportions to obtain certain desirable properties.
(iv) The tendency of an atom to attract electrons to itself when combined in a compound.
(v) The reaction in which carboxylic acid reacts with alcohol in the presence of cone. H₂SO₄ to form a substance having a fruity smell.
Answer:
(i) Single covalent bond
(ii) Thin strip of pure copper
(iii) Alloys
(iv) electronegativity
(v) esterification

(h) Fill in the blanks from the choices given in brackets: [5]
(i) The polar covalent compound in gaseous state that does not conduct electricity is ………………….. .
(carbon tetra chloride, ammonia, methane)
Answer:
Ammonia

(ii) A salt prepared by displacement reaction is ………………………. .
(ferric chloride, ferrous chloride, silver chloride)
Answer:
Ferrous chloride

(iii) The number of moles in 11 gm of nitrogen gas is ………………………. .
(0.39, 0.49, 0.29) [atomic mass of N = 14]
Answer:
0.39

(iv) An alkali which completely dissociates into ions is ………………………. .
(ammonium hydroxide, calcium hydroxide, lithium hydroxide)
Answer:
Ammonium hydroxide

(v) An alloy used to make statues is ………………………. .
(bronze, brass, fuse metal)
Answer:
Bronze

[Section – II (40 MARKS)]
(Attempt any four questions from this Section)

Question 2.
(a) The following table represent the elements and the atomic number.
With reference to this answer the following using only the alphabets given in the table. [3]

Element	Atomic number
P	13
Q	7
R	10

(i) Which element combines with hydrogen to form a basic gas ?
(ii) Which element has an electron affinity zero ?
(iii) Name the element, which forms an ionic compound with chlorine.
Answer:
(i) Q (It forms ammonia which is basic)
(ii) R (because it is a noble gas)
(iii) P (because it has a positive charge of +3)

(b) Draw the electron dot diagram for the compounds given below. Represent the electrons by (.) and (x) in the diagram. [3]
[Atomic No. : Ca = 20, O = 8,
Cl = 17, H =1]
(i) Calcium oxide
(ii) Chlorine molecule
(iii) Water molecule
Answer:

(c) Choose the correct word which refers to the process of electrolysis from A to E, to match the description (i) to (iv) : [4]
A : Oxidation
B : Cathode
C: Anode
D : An electrolyte
E: Reduction
(i) Conducts electricity in aqueous or in molten state.
(ii) Loss of electron takes place at anode.
(iii) A reducing electrode.
(iv) Electrode connected to the positive end or terminal of the battery.
Answer:
(i) An electrolyte
(ii) Oxidation
(iii) Anode
(iv) Cathode

Question 3.
(a) Baeyer’s process is used to concentrate bauxite ore to alumina. [3]
Give balanced chemical equations for the reaction taking place for its conversion from bauxite to alumina.
Answer:
Al₂O₃.2H₂O + 2NaOH → 2NaAIO₂ + 3H₂O
NaAIO₂ + 2H₂O → NaOH + Al(OH)₃↓

Baeyer’s process is used to concentrate bauxite ore to alumina by treating it with sodium hydroxide.

(b) Complete the following by selecting the correct option from the choices given. [3]
(i) pH of acetic acid is greater than dilute sulphuric acid. So acetic acid contains …………………………. concentration of
H⁺ ions, (greater, same, low).
(ii) The indicator which does not change colour on passage of HCl gas is …………………. (methyl orange, moist blue litmus, phenolphthalein)
(iii) The acid which cannot act as an oxidizing agent is ………………………….. .
(conc. H₂SO₄, conc. HNO< sub>3, cone. HCl).
Answer:
(i) low
(ii) phenolphthalein
(iii) conc.H₂SO₄

(c) Match the gases given in column I to the identification of the gases mentioned in column II: [4]

Column I	Column II
(i) Hydrogen sulphide	A.    A. Turns acidified potas­sium dichromate sol­ution green.
(ii) Nitric oxide	B.    B. Turns lime water milky.
(iii) Carbon dioxide	C.    C.  Turns reddish brown when it reacts with oxygen.
(iv) Sulphur dioxide	D.    D. Turns moist lead acetate paper silvery black.

Answer:
(i) → D
(ii) → C
(iii) → B
(iv) → A

Question 4.
(a) Differentiate between the following pairs based on the information given in the brackets. [3]
(i) Conductor and electrolyte (conducting particles)
Answer:

Conductor	Electrolyte
The Conducting parti­cles in conductor are the electrons.	The Conducting part­icles in an electrolyte are cations and anions.

(ii) Cations and anions (formation from an atom)
Answer:

Cations	Anions
Cations are formed by losing of electrons from the neutral isolated gaseous atoms.	Anions are formed by gaining of electrons by the neutral isolated gaseous atoms.

(iii) Acid and Alkali (formation of type of ions)
Answer:

Acid	Alkali
Acids are the compou­nds’ which when dissolved in water furnish hydrogen / hydronium ions as the only positively charged ions. HCl + H2O → H30+ + Cl–	Alkalis are the compou­nds which when dissolved in water furnish hydroxyl ions as the only negatively charged ions. NH4OH → NH4+ + OH–

(b) Draw the structures of isomers of pentane. [3]
Answer:

(c) Hydrogen chloride gas is prepared in the laboratory using concentrated sulphuric acid and sodium chloride. Answer the questions that follow based on this reaction : [4]
(i) Give the balanced chemical equation for the reaction with suitable conditions) if any.
Answer:

(ii) Why is concentrated sulphuric acid used instead of concentrated nitric acid ?
Answer:
Conc. nitric acid is not used during the preparation of HCl because it is volatile and may volatilize out along with hydrogen chloride.

(iii) How is the gas collected ?
Answer:
Hydrogen chloride is collected by upward displacement of air.

(iv) Name the drying agent not used for drying the gas.
Answer:
It is dried by passing through concentrated sulphuric acid.

Question 5.
(a) Distinguish between the following pairs of compounds using a reagent as a chemical test: [3]
(i) Calcium nitrate and Zinc nitrate solution.
Answer:

Calcium nitrate	Zinc nitrate
When sodium hydroxide is added, white precipitates of calcium hydroxide are formed. Ca(NO3)2 + 2NaOH → Ca(OH)2 (white ppt.) + 2NaNO3	When sodium hydroxide is added, gelatinous white ppt. of zinc hydroxide are formed. These precipitates dissolve in excess of sodium hydroxide to form sodium zincate. Zn(NO3)2 + 2NaOH → Zn(OH)2 + 2NaNO3 Zn(OH)2 + 2NaOH → Na2ZnO2 + H2O

(ii) Ammonium sulphate crystals and Sodium sulphate crystals.
Answer:

Ammonium sulphate crystals	Sodium sulphate crystals
Add sodium hydroxide to ammonium sulphate crystals and heat. (NH4)2SO4 + 2NaOH → Na2SO4 + 2H2O + 2NH3↑	Add sodium hydroxide to sodium sulphate crystals and heat. Na2SO4 + NaOH → No reaction is observed

(iii) Magnesium chloride and Magnesium nitrate solution.
Answer:

Magnesium chloride	Magnesium nitrate
Add silver nitrate solution to magnesium chloride. MgCl2 + 2AgNO3 → Mg(NO3) 2 + 2AgCl↓ Curdy white precipitates of silver chloride will be formed.	Add silver nitrate solution to magnesium nitrate. Mg(NO3)2 + AgNO3 → No reaction No precipitates are formed.

(b) Calculate the percentage of: [3]
(i) Fluorine
(ii) Sodium and
(iii) Aluminium
in sodium aluminium fluoride [Na₃AIF₆], to the nearest whole number.
[Atomic Mass : Na = 23, Al = 27, F = 19]
Answer:
Na₃AlF₆
3(23)+ 1(27)+ 6(19) = 210 . 114
(i) % of Fluorine = \(\frac{114}{210}\) × 100 = 54.28%
(ii) Sodium = \(\frac{69}{210}\) × 100 = 32.85%
(iii) Aluminium = \(\frac{27}{210}\) × 100 = 12.85%

(c) (i) State the volume occupied by 40 gm of methane at STP, if its vapour density (V.D.) is 8. [4]
(ii) Calculate the number of moles present in 160 gm of NaOH.
[Atomic Mass : Na =23, H = 1, O = 16]
Answer:
(i) V. D of Methane = 8
Molecular Mass = 2 × V.D. = 2 × 8 = 16 gm
16 gm of methane occupies of 22.4 l at S.T.P.
1 gm of methane occupies a volume of \(\frac{22.4}{16}\)
40 gm of methane occupies a volume of \(\frac{22.4}{16}\) × 40 = 56 gm

(ii) Molecular mass of NaOH = 23 + 1 + 16 = 40
40 gm of NaOH equal to 1 mole
1 gm of NaOH equal to \(\frac{1}{40}\)
160 gm of NaOH equal to \(\frac{1}{40}\) × 160 = 4 moles

Question 6.
(a) Identify the salts, P, Q, R from the following observations: [3]
(i) Salt P has light bluish green colour. On heating, it produces a black coloured residue. Salt P produces brisk effervescence with dil. HCl and the gas evolved turns lime water milky, but no action with acidified potassium dichromate solution.
Answer:

(ii) Salt Q is white in colour. On strong heating, it produces buff yellow residue and liberates reddish brown gas. Solution of salt Q produces chalky white insoluble precipitate with excess of ammonium hydroxide.
Answer:

(iii) Salt R is black in colour. On reacting with concentrated HCl, it liberates a pungent greenish yellow gas which turns moist starch iodide paper blue black.
Answer:

(b) Identify the substance underlined in each of the following: [3]
(i) The electrode that increases in mass during the electro refining of silver.
(ii) The acid that is a dehydrating as well as a drying agent.
(iii) The catalyst used to oxidize ammonia into nitric oxide.
Answer:
(i) cathode
(ii) sulphuric acid
(iii) platinum

(c) Copy and complete the following paragraph using the options given in brackets:
Akenes are a homologous series (i) ……………….. (saturated/unsaturated) hydrocarbons characterized by the general formula
(ii) …………………… (C_nH_2n+2/C_nH_2n). Alkenes undergo
(iii) …………………… (addition/substitution) reactions and also undergo (iv) …………………… (hydrogenation/dehydrogenation) to form alkanes.
Answer.
(i) unsaturated
(it) C_nH_2n
(iii) addition
(iv) hydrogenation

Question 7.
(a) Write balanced chemical equations, for the preparation of the given salts (i) to (iii) by using the methods A to C respectively. [3]
A. Neutralization
B. Precipitation
C. Titration
(i) Copper sulphate
(ii) Zinc carbonate
(iii) Ammonium sulphate
Answer:
(i) Copper sulphate
Neutralisation
CuO + H₂SO₄ → CuSO₄ + H₂O
(ii) Zinc carbonate Precipitation
ZnCl₂ + Na₂CO₃ → ZnCO₃↓ + 2NaCl
(iii) Ammonium Sulphate Titration
2NH₄OH + H₂SO₄ → (NH₄)₂SO₄ + 2H₂O

(b) Name the following elements : [3]
(i) An alkaline earth metal present in group 2 and period 3.
(ii) A trivalent metal used to make light tools.
(iii) A monovalent non-metal present in fluorspar.
Answer:
(i) Magnesium
(ii) Aluminium
(iii) Fluorine

(c) An aqueous solution of nickel (II) sulphate was electrolyzed using nickel electrodes. Observe the diagram and answer the questions that follow: [4]

(i) What do you observe at the cathode and anode respectively ?
(ii) Name the cation that remains as a spectator ion in the solution.
(iii) Which equation for the reaction at the anode is correct?
1. Ni → Ni²⁺ + 2e^–
2. Ni + 2e^– → Ni²⁺
3. Ni²⁺ → Ni + 2e^–
4. Ni²⁺ + 2e^– → Ni
Answer:
(i) Anode gets thinner because of the dissolution of nickel electrode into the solution.
Cathode gets thicker due to deposition of nickel metal on the electrode.
(ii) hydrogen ion
(iii) (1) Ni → Ni²⁺ + 2e^–