Question

what are pollen grains and how

Answer 1

Pollen is a fine to coarse powdery substance comprising pollen grains which are male microgametophytes of seed plants, which produce male gametes.. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination.

Answer 2

pollen grains are the male gametes in anther which ho in stigma by process of pollination