Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

A colour–blind man marries a woman with normal vision whose father was colour–blind. Work out a cross to show the genotype of the couple and their respective sons.

Sometimes due to biotic/ abiotic factor the climax remain in a particular seral stage (preclimax) without reaching the climax. Do you agree with this statement. If yes, give a suitable example.

Name two liquid household products obtained by microbial activity.

What are hallucinogens? Give their two examples. Mention their clinical use, if any.

Name the ancestors of man based on the features given below:

1. Human-like meat eater with 900cc brain, lived in Java.
2. More human with brain size 1400cc, lived in Central Asia, used hides and buried their dead.
3. Human-like, vegetarian, with brain capacity between 650cc and 800cc.
4. Man-like primate, that existed about 15 mya. Fossils found in Tanzania.

A woman of 47 years, delivered an abnormal child with flattened nasal bridge and mouth usually open with a large protruding tongue. Name this genetic abnormality. What causes this condition?

Give diagrammatic representation of decomposition cycle in a terrestrial ecosystem.

A man with blood group A married a woman with B group. They have a son with AB blood group and a daughter with blood group O. Work out the cross and show the possibility of such inheritance.

Explain : Chitinase

What do you mean by biodiversity? What is the importance of species biodiversity in ecosystem?