Select and write analogous structures from the list given below:

(i) Wings of butterfly and birds

(ii) Vertebrate hearts

(ii) Tendrils of bougainvillaea and Cucurbita

(iv) Tubers of sweet potato and potato

Explain the mechanism of ‘sex determination’ in birds. How does it differ from that of human beings?

How has the use of Agrobacterium as vectors helped in controlling Meloidogyne incognita infestation in tobacco plants? Explain in the correct sequence.

Organic farmers prefer the biological control of diseases and pests of the use of chemicals for the same purpose. Justify.

Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered throughout the cell. Explain.

Explain outbreeding, outcrossing and cross-breeding practices in animal husbandry.

“India has greater ecosystem diversity than Norway.” Do you agree with the statement? Give reasons in support of your answer.

Write the difference between genetic biodiversity and species biodiversity that exists at all the levels of biological organisation.

With the help of an algebraic equation, how did Hardy-Weinberg explain that in a given population the frequency of occurrence of alleles of a gene is supposed to remain the same through generations?

Differentiate between analogous and homologous structures.