CBSE Class 12 Biology Sample Paper 2018 (5). It’s always recommended to practice as many sample papers as possible before the examinations. Students can download the sample papers and also question papers of previous years to practice and score better marks in examinations. Refer to other links too for more sample papers.
Section - A
1. A tissue culture experiment has been performed with a plant tissue infected with TMV. Meristematic tissue produces healthy plant. Reason out the possibility of obtaining such result. 1
2. State a method of cellular defence which works in all eukaryotic organisms. 1
3. In case of an infertile couple, the male partner can inseminate normally but the mobility of sperms is below 40 percent. Judge, which kind of ART is suited in this situation to form an embryo in the laboratory, without involving a donor? 1
4. Calculate the length of the DNA of bacteriophage lambda that has 48502 base pairs. 1
5. If two genes are located far apart from each other on a chromosome, how the frequency of recombination will get affected?
Section - B
6. The alarming population growth is leading to scarcity of basic requirements. Enumerate and justify any two population control measures to overcome this problem. 2
7. Both Down’s syndrome and Turner’s syndrome are examples of chromosomal disorders. Cite the differences between the two. 2
8. Demand for mushroom as food has led to its culturing on a large scale. Similarly, it is perceived that microbes too would become acceptable as food. Identify a microbe which can be cultured as a food source and give the applicability of its culture in the given context. 2
Success rate of artificial insemination in cattle is fairly low. Identify any other mean to improve the successful production of hybrids. State the advantages of this technique. 2
9. a) Patients who have undergone myocardial infarction are given clot buster. Mention the clot buster administered and its microbial source.
b) A person recuperating from illness is advised to have curd regularly. Why? 1+1
10. Interpret two effects of loss of biodiversity in a region. 2
Section - C
11. Draw and label the enlarged view of microsporangium. State the function of its innermost layer. 3
12. a) State the type of gametes shown in the diagram.
b) Identify the process taking place and the resultant structure.
c) Name an organism that reproduces in this manner. 1+1+1
13. Diagrammatically represent the experimental set up that proves Oparin - Haldane hypothesis.
14. A cross is made between different homozygous pea plants for contrasting flower positions.
a) Find out the position of flowers in F1 generation on the basis of genotypes.
b) Work out the cross upto F2 generation.
c) Compute the relative fraction of various genotypes in the F2 generation? 1+1+1
15. Refer to the figure given below and answer the questions that follow:
a) Recognize and explain the process by which Tasmanian wolf evolved.
b) Give one example of an animal that has evolved along with Tasmanian wolf.
c) Compare and contrast the two animals shown? 1+1+1
16. Your classmate complains of headache and cough to the doctor. The doctor confirms that he is suffering from Pneumonia and not just common cold. How the doctor must have reached to such conclusion? Mention any two precautions to be followed to prevent the spread of this disease. 3
17. Cow dung and water is mixed and the slurry is fed into the biogas plant for digestion by microbes. The person performing the process shares that there is no need to provide inoculum for it, why? What is the role of microbes at the source? Under which condition will they be most active and effective? 3
18. A person is born with a hereditary disease, suggest the possible corrective method for it. Illustrate by giving a specific example. 3
19. A doctor prescribed morphine as a sedative and pain killer to your cousin who has undergone surgery. Even after recovery he continued to consume the prescribed medicine. What do you conclude about his condition? After appraising yourself, what measures will you suggest to him to control this problem? Briefly explain any two.
Please click the link below to download CBSE Class 12 Biology Sample Paper 2018 (5).