students must start practicing the questions from CBSE Sample Papers for Class 12 Biology with Solutions Set 11 are designed as per the revised syllabus.
CBSE Sample Papers for Class 12 Biology Set 11 for Practice
Time Allowed: 3 Hours
Maximum Marks: 70
General Instructions:
- All questions are compulsory.
- The question paper has five sections and 33 questions. All questions are compulsory.
- Section-A has 16 questions of 1 mark each: Section-B has 5 questions of 2 marks each; Section- C has 7 questions of 3 marks each; Section- D has 2 case-based questions of 4 marks each: and Section-E has 3 questions of 5 marks each.
- There is no overall choice. However, internat choices have been provided in some questions. A student has to attempt onty one of the alternatives ¡n such questions.
- Wherever necessary, neat and properly Labeled diagrams should be drawn.
Section – A (16 Marks)
Question 1.
Which of the following is not an example of homologous organs?
(a) Thorns of Bougainvillea
(b) Tendrils of Pass/flora
(c) Phylloclade of Opuntia
(d) Tendrils of Pisum
Question 2.
What is not true for sporopollenin?
(a) It is hardest
(b) Resistant
(c) Can withstand high temperature
(d) It is an inorganic material
Question 3.
Which difference between monocarpellary and multi-carpellary gynoecium is not true?
| Multicarpellary Gynoecium | Monocarpetlary Gynoeciurn |
| (a) More than one pistil | Single pistil |
| (b) Seen in leguminous plants | Seen in Malvaceae |
| (c) Syncarpous | Monocarpous |
| (d) Example: Tulip | Example: Mango |
Question 4.
Which is true for the following figure?
| (a) Head | Contains diploid nucleus |
| (b) Head | Has acrosome structure |
| (c) Acrosome | Filled with lysosomes |
| (d) Acrosome | Helps in the movement of sperm |
Question 5.
Name the microbe which is responsible for large holes in Swiss cheese.
(a) Propionibacterium sharmanii
(b) Lactobacillus
(c) Saccharomyces cerevisiae
(d) None of the above
Question 6.
Identify the correct statements:
(a) Helicase is responsible for unwinding the DNA helix
(b) DNA ligase joins the Okazaki fragments.
(c) Both (a) and (b)
(d) None of the above
Question 7.
Which type of chromosomal mutation is shown in the figure below?
(a) DeLetion
(c) Somatic
(b) Inversion
(d) Duplication
Question 8.
Sweet potato and potato are:
(a) Support for ontogeny recapitulates phylogeny
(b) Homologous structures
(c) Vestigial organs
(d) Analogous organs
Question 9.
Match the following columns and select the correct option.
| Column (I) | Column (ii) |
| (A) Clostridium bretylium | Cyclosporin-A |
| (B) Trichoderma po1 ysporum | Butyric Acid |
| (C) Monascus purpureus | Citric Acid |
| (D) Aspergillus niger | Blood cholesterol Lowering agent |
(a) (A)-(ii), (B)-(i), (C)-(iv), (D)-(iii)
(b) (A)-(i), (B)-(iii), (C)-(ii), (D)-(iv)
(c) (A)-(ii), (B)-(iii), (C)-(i), (D)-(iv)
(d) (A)-(iv), (B)-(ii), (C)-(iii), (D)-(i)
Question 10.
identify the protozoan disease.
(a) Malaria
(b) Ascariasis
(c) Ringworm
(d) Cancer
Question 11.
Identify the correct statement.
(a) Exonuclease cut DNA flom the ends
(b) Endonuclease cut DNA at specific site
(c) Both (a) and (b)
(d) None of the above
Question 12.
Reena’s mother wants to make curd. So she boiled milk and added a spoon of curd to it. Lactic acid bacteria (LAB) acts as an inoculate when added to warm milk leading to coagulation of milk, identify the incorrect benefits of LAB.
(a) Check disease-causing microbes
(b) Improves nutritive quality of milk
(c) Add important enzymes to milk
(d) All of these 1
Question No. 13 to 16 consist of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below:
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true and R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Question 13.
A significant class of RNA molecules is represented by transfer RNAs (tRNAs). Their main job is to aid in the decoding of a messenger RNA (mRNA) sequence necessary for protein synthesis, which guarantees the accurate translation of genetic information imprinted in DNA. When little was known about the main dogma of molecular biology, the discovery of tRNA in the late 1950s offered crucial insight into genetic machinery.
Assertion (A): The tRNA brings the amino acids and reads the genetic code.
Reason (R): In bacteria, only one type of RNA is involved in the process of transcription,
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true and R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Question 14.
Assertion (A): The Darwin’s finches have a diversity of beak shapes that are suitable for consuming huge seeds, flying insects, and cactus seeds.
Reason (R): The ancestors of Darwin’s finches, which consume seeds, spread out from the continent of South America to various Galapagos Island regions, where they discovered fresh environments devoid of rivals.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true and R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Question 15.
Assertion (A): Biologists are not sure about the total number of prokaryotic species in the world.
Reason (R): Conventional taxonomic methods are not suitable for identifying microbial species.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true and R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Question 16.
Assertion (A): Fishes and insects come under the category of conformers. reguLate and fixed internal.
Reason (R): They can maintain a temperature.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true and R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Section – B (10 Marks)
Question 17.
In the given figure which marked number (1,2, 3,4) is tied and cut to block fertilization. Explain.
Question 18.
Study the figures given beLow and answer the question.
Determine which of the crosses has the strongest gene-to-gene Linkage. Give justifications for your response.
Question 19.
Write
(A) Causative organism of Ascarasis and Its symptoms.
(B) PossibLe mode of transmission.
Question 20.
What are the prerequisites for a molecule to act as a genetic material?
OR
Describe the events of copping and toiling which happen during the process of transcription.
Question 21.
History has historically reassured us of a reassuring order to things through scientific study of human evolution. It has portrayed people as being more Intelligent, cunning, and compassionate than our ancestors.
(A) Where was the first man-Like animal found?
(B) Write the scientific name for the first primitive mon.
Section – C (21 Marks)
Question 22.
Give reasons:
(A) Apple is a false fruit.
(B) Wheat seeds are albuminous.
(C) Pollen grains are well preserved as fossils.
Question 23.
Komal was on a visit to a village area. He went to the village school Unfortunately, the biology teacher was on Leave. He asked the principal to share the topic that was supposed to be taught that doy to the students. He has to teach the mechanism of sex determination in humans. Help him teach the students by describing the aforementioned mechanism.
Question 24.
DiagrammaticaLly iLlustrate the steps In formation of recombinant DNA by action of restriction endonucLease: EcoRI.
Question 25.
Explain the process of the secondary treatment of sewage by the micrr,bes.
Question 26.
Based on the given graph showing the number of organisms with particular temperature characteristics, answer the
quatlons that follow
(A) Which region has more conformers?
(B) Which region has more regulators?
(C) Draw a graph illustrating organismic response at external and internal levels w.r.t. changes in abiotic factors.
OR
What is homeostasis? Differentiate between regulators and conformers with examples.
Question 27.
In the above figure:
(A) Identify (i), (ii), and (iii).
(B) Using the given figure, explain the process to select transformants from non-transformants.
Question 28.
How do the following organisms adapt to unfavorable conditions for their survival?
(A) Snails
(B) Seeds
(C) Bears
(D) Zooplanktons
(E) Fungi
(F) Bacteria
Section – D (8 Marks)
Q. No. 29 and 30 are case-based questions. Each question has subparts with internal choice in one subpart.)
Question 29.
The above graph depicts the process of get electrophoresis for separation of DNA fragments. Based on your previous knowledge and inferences from the graph, answer the following questions:
(A) Which of the DNA fragments moved the farthest?
(B) DNA fragments move towards which electrode?
(C) How the separated DNA fragments can be visualised after staining?
OR
(C) What is the result of UV exposure after staining with Ethidium bromide?
Question 30.
The transfer of genetic information from DNA to mRNA is called transcription. The DNA segment that takes part in it includes a promoter, structural gene and a terminator. Promoter sequences are present upstream to the transcriptional unit. RNA polymerase, having three sites i.e. Sigma, core complex, Rho brings about transcription. There are non-coding sequences in eukaryotic genes called Junk DNA. Exons are the coding sequences white the Introns are the noncoding ones. The synthesised strand of mRNA has some intronic unwanted sequences which are removed by Splicing. Splicing involves capping, polyadenylation and hnRNA tailoring.
(A) Write any two functions of tRNA.
(B) Why does splicing occurs?
(C) What are the tRNA’s primary components?
OR
Capping, during the post-transcriptional processing, takes place at which end? 2
Section – E (15 Marks)
Question 31.
The following figure shows the human foetus within the uterus in humans. On the basis of the given figure, answer the questions that follow:
(A) Identify (i) and (ii).
(B) Which hormones are produced by the human placenta?
(C) Inner cell mass differentiates into some layers. Mention the layers.
(D) Where are the stem cells present? Why are they important?
(E) Which part of the body is primarily responsible for secretion of relaxin?
OR
Based on your observations of the above graph, answer the following questions:
(A) Which of these hormones are involved in the hormonal control of the menstrual cycle? Mention their functions.
(B) Differentiate between menarche and menopause.
Question 32.
Explain the structural formulation/ organisation of a nucleosome in eukaryotes.
OR
How did Messelson and Stahl manage to prove the semi-conservative mode of DNA replication?
Question 33.
Shravan has been detected with malaria. His sister was curious about the disease and the life cycle of its causative organism. She tried to draw the life cycle of causative organism as shown:
Help her in learning about the life cycle of the causative organism of malaria.
OR
Kabir is studying some of the lymphoid organs for his biology test. Help him in knowing about the structural and functional role of bone marrow, spleen, thymus, and the lymph nodes.