Human Health and Disease — BIOLOGY STD 12 Science — Question

Heat loss or heat gain depends upon the surface area of the organism's body. Explain with the help of a suitable example.

OR

Explain, why are small animals rarely found in the polar regions?

In GIFT, gametes are transferred to the fallopian tube. Can gametes be transferred to the uterus to achieve the same result? Explain.

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.

Write short notes on :
(a) Photochemical Oxidants
(b) Incineration Pyrolysin
(c) Reverse Osmosis

Arrange the following primates in correct sequence of evolution to man-

1. Dryopithecus.
2. Australopithecus.
3. Homo erectus.
4. Homo habilis.
5. Homo sapiens.
6. Cro-Magnon man.
7. Ramapithecus.

Are the restriction endonucleases found in eukaryotic cells? Justify your answer.

What would happen to the successive trophic levels in the pyramid of energy, if the rate of reproduction of phytoplanktons was slowed down? Suggest two factors which could cause such a reduction in phytoplankton reproduction.

How does a test-cross help in identifying the genotype of the organism? Explain.

Explain the response initiated when a dose of vaccine is introduced into the human body.

Describe the situations in which independent assortment of genes results in 50% recombination.