When and where do chorionic villi appear in humans? State their function.
Chorionic villi appear on the trophoblast after implantation. Chorionic villi interdigitate with the uterine tissues and jointly forms the placenta which is a structural and functional unit between developing embryo and maternal body.
Name the enzyme and state its property that is responsible for continuous and discontinuous replication of the two strands of a DNA molecule.
Why is the enzyme cellulase needed for isolating genetic material from plant cells and not from the animal cells?
An anther with malfunctioning tapetum often fails to produce viable male gametophytes. Give any one reason.
Geitonogamous flowering plants are genetically autogamous but functionally cross-pollinated. Justify.
Identify the examples of convergent evolution from the following:
(i) Flippers of penguins and dolphins
(ii) Eyes of octopus and mammals
(iii) Vertebrate brainsName the type of biodiversity represented by the following:
(a) 50,000 different strains of rice in India.
(b) Estuaries and alpine meadows in India.