Molecular basis of Inheritance — BIOLOGY STD 12 Science — Question

Assertion : A network of food chains existing together in an ecosystem is known as food web.
Reason : An animal like kite cannot be a part of a food web.

What happens during fertilization in humans after many sperms reach close to the ovum?

When the pollen of a flower is transferred to the stigma of another flower on the same plant, the process is known as:

Fertilizers applied to crop plants, pollute:

Double fertilization is a characteristic of

_______ is a procedure through which a piece of DNA is introduced in a host bacterium.

Use of spermicidal creams, jellies and foams along with diaphragms, cervical caps and vaults leads to

All of the following conditions were present on early earth, except