Question
Define pollination. Explain any two contrivances of self-pollination.

Answer

Pollination : The transfer of pollen grains from anther to stigma of pistil is called pollination.
Two contrivances found in self-pollinated flower are as given below :
(1) Bisexuality : Such flowers possess both male and female sex organs and hence promote selfpollination.
(2) Homogamy : When male and female sex organs develop and mature at the same time it favours self-pollination, e.g. Mirabilis, catharanthus.
(3) Cleistogamy : Those flowers which never open at all, are called cleistogamous flower hence these occurs only self-pollination in them as a rule e.g. viola, commelina, oxalis etc.

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