Subject

Biology

Class

CBSE Class 12

Pre Boards

Practice to excel and get familiar with the paper pattern and the type of questions. Check you answers with answer keys provided.

Sample Papers

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 Multiple Choice QuestionsShort Answer Type

11.

(a) Can a plant flowering in Mumbai be pollinated by pollen grains of the same species growing in New Delhi ? Provide explanations to your answer.

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12.

Both Haemophilia and Thalassemia are blood related disorders in humans. Write their causes and the difference between the two. Name the category of genetic disorder they both come under.

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13.

(a) List the two methodologies which were involved in human genome project. Mention how they were used.
(b) Expand ‘YAC’ and mention what was it used for.

1515 Views

14.

Write the characteristics of Ramapithecus, Dryopithecus and Neanderthal man.

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15.

Name a human disease, its causal organism, symptoms (any three) and vector, spread by intake of water and food contaminated by human faecal matter.

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16.

(a) Write the desirable characters a farmer looks for in his sugarcane crop. (b) How did plant breeding techniques help north Indian farmers to develop cane with desired characters ?

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17.

Secondary treatment of the sewage is also called Biological treatment. Justify this statement and explain the process

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18.

(a) Explain the significance of palindromic nucleotide sequence in the formation of recombinant DNA.
(b) Write the use of restriction endonuclease in the above process.

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19.

Describe the roles of heat, primers and the bacterium Thermus aquaticus in the process of PCR.

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20.

Explain the various steps involved in the production of artificial insulin.


* Insulin contains two short polypeptide chains: chain A and chain B linked together by disulphide bridges.
* In mammals insulin is synthesised as a pro-hormone. It contains an extra stretch called C-peptide.
* C-peptide is absent in the mature insulin and is removed during maturation into insulin.
* Production of insulin by rDNA techniques was achieved by an American company, Eli Lilly in 1983. It prepared two DNA sequences corresponding to A and B, chains of human insulin and introduced them in plasmids of E. coli for production. The A and B chains produced were separated, extracted and combined, by creating disulfide bonds to form human insulin.

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