question_answer

Pollination is not necessary in apomixis. Give reason.

Or

Human placenta acts as a structural and functional unit between the foetus and maternal body. Justify the statement by giving any two basic functions it performs.

Answer:

Apomixes is a form of asexual reproduction that mimics sexual reproduction. In It, seeds are produced without fertilisation. It does not involve formation of zygote through the gametic fusion. Pollination is necessary for the transfer of male gamete of a plant to pistil of another plant of same species for fusion. As gametic fusion does not occur in apomixis, pollination is not necessary. It occurs in some species of Asteraceae and grasses.

Or

Human placenta acts as a structural and functional unit between the foetus and maternal body. It performs many important functions. Some of them are as follows

(i) It facilitates the supply of oxygen and nutrients to the embryo.

(ii) It secretes hormones that are necessary to maintain pregnancy, e.g. hCG, hPL, oestrogen, progesterone, etc.