Human Health and Disease — BIOLOGY STD 12 Science — Question

Mention the pollinating agent of an inflorescence of small dull coloured flowers with well exposed stamens and large feathery stigma. Give any one characteristic of pollen grains produced by such flowers.

What do you mean by emigration?

What is adaptive radiation?

Give an example where animal-plant interaction involves co-evolution.

Khorana and his colleagues synthesized an RNA molecule with repeating sequence of AG nitrogenous bases (AG AG AG AG AG AG). It produced a tetrapeptide with alternating sequence of valine and tyrosine. It proves that codon for valine and tyrosine are?

Write the phenotypic ratio of the F, progeny of a cross, involving polygenic trait controlled by three separate genes.

Give the name of causative organism and diagnostic test for AIDS.

How is the length of DNA usually defined?

In a certain group of insects, some have 17 chromosomes and some have 18 chromosomes. Write about the gender of these two types of insects.

What are biosphere reserves? Mention the importance of setting up of biosphere reserves.