CBSE Class 12 Biology Sample Paper Set-12

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CBSE Class 12 Biology
Sample Paper
Set-12


CBSE Sample Papers for Class 12 Biology Solved 2016 Set 12

Section A

1.Reproductive and child healthcare programme has been made by the government of India to each people and create awareness about reproduction related aspects. State one major task of such programme.

2.State the way of predicting a genotype of an organism exhibiting a dominant phenotype trait.

3* Macrophages plays an important role in providing immunity to the humans. Discuss.

4.After performing certain experiments on Drosophila, TH Morgan came to a conclusion that the phenotypic ratio of F2 population tends to deviate from a normal 9:3:3:1. How did he made this conclusion?

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5.Mention the cause of occurrence of snowblindness in human beings.

Section B

6.Lac operon is considered to be regulated by its substrate. Explain.

Or

Mention the key concepts about the mechanism of biological evolution/speciation according to

  • deVries (ii) Darwin

7.Cite out the differences between the types of male and female gametocytes found in human being.

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8.Reeta went for a MTR Doctor diagnosed and tell her that she is carrying a foetus been developed by an XX-egg being fertilised by a Y-carrying sperm. What do you understand by this situation?

9.Ecosan toilets are being functional in Kerala and Sri Lanka. State the role played by them in conserving environment.

10. It has been noticed since years that chemical pesticides and insecticides are responsible for polluting the environment. Justify.

Section C

11. Does according to you, the alternate splicing of exons may enable a structural gene coding for several iso-proteins from one and the same gene? If yes, how ? If no, why so?

12. Plasmid is a boon to biotechnology. Justify the statement quoting the production of human insulin as an example.

13. Kartik have isolated and identified a useful gene in a bacterium. Now, how will you prepare a flow chart of the steps following the transfer of this gene to a plant?

14. Observe the type of the ecological pyramid given below. Also give one example each of pyramid of number and pyramid of biomass in such cases.

CBSE Sample Papers for Class 12 Biology Solved 2016 Set 12

Or

Mention the pioneer and the climax species in a water-body ecosystem. Highlighting the changes observed in the biomass and the biodiversity of the successive serai community been developed in the water-body.

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15. Bioactive molecules of fungal origin helps in restoring good health of human. Justify.

16. It is often seen that honeybees produces their young ones only by sexual reproduction. Inspite of this, in a colony of bees, both haploid and diploid individuals are also found. Explain how?

17. Differentiate between the process of spermatogenesis and spermiation in human males.

18. In an angiosperm, the embryo sac is haploid, zygote is diploid and endosperm is triploid. Justify the statement giving reasons of each stage.

19. If you are a manager of a dairy farm. What measures would you undertake to improve the quality and quantity of milk production?

20. Cite the differences between the following terms related to the molecular inheritance.

  • Repetitive DNA and satellite DNA
  • mRNA and small fRNA
  • Template strand and coding strand

21. The developed countries are often related to the biopiracy cases when compared to the underdeveloped or developing countries. Explain the statement giving an example justifying it.

22. The hnRNA undergoes additional process after the completion of process of transcription in eukaryotes. Mention the two such processes.

Section D

23. Akshay was concerned about the pollution being made by the unnecessary horns of buses cars and other vehicles in the residential area.

He along with his friends decided to make their area a ‘no noise have’. For this they meet with the senior authorities and put forth the issue in front of them.

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Discuss the major causes, effects of it. Also share some measures to control it. Keeping in mind about the ill effects of noise pollution.

Section E

24. Ankit had been to Hyde’ ibad for his vacations at his cousins place. He demanded to eat chicken out there. His cousin denied to take him out for eating non-veg as he told him that it is not safe to eat chicken these days due to bird flu.

Mention the harmful action of bird flu and the different ways to present the spread of this disease.

Or

Selective breeding of animals is mainly done to increase the possibility of the animals to obtain a desired trait in the resulted offspring. Discuss the ways being employed to achieve a successful animal breeding. Also mention which is the best method out of these being discussed and why?

25. (i) Radhika visited a hill station with her family. Everyone out there was

complaining for shortness of breath and some other problem. Discuss the fact behind. Why the tourists visiting high altitude places or mountains are advised to resume normal ‘active life’ only after a few days of reaching there?

  • Is it possible to find small animals in the polar regions? Give reasons.

Or

  • Draw an ideal pyramid of energy upto four trophic levels where 1,000,000 J are available from sunlight to the primary producer. Indicate the amount of energy available at each trophic level.
  • Pyramid of energy always upright. When compared to the pyramid of number of biomass? Explain.
  • Discuss the major limitations of an ecological pyramid.

26. A true breeding pea plant homozygous for axial violet flowers (AAW) is allowed to crossed with another pea plant with terminal white flowers (aaw).

  • Predict out the phenotype and genotype of Fx-generation.
  • Find out the phenotypic ratio of F2-generation.
  • Discuss the Mendel’s generalization that can be derived from the above cross.

Or

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Workout a cross between a homozygous tall pea plant with green seeds and dwarf pea plant with yellow seeds.

  • Find out the phenotype and genotype of F1-generation.
  • Also predict out the phenotypic ratio of F2-generation with the help of a Punnett square.

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