∞ generated and posted on 2016.08.30 ∞

Male gametophyte-containing structures of seed-bearing plants.

Pollen is produced by sporangium-equivalent plant organs known as microsporangia since they produce the smaller of the gametophytes, that which produces the sperm (more correctly stated, microsporangia produce the smaller of the spores that go on to produce the male gametophyte).

The pollen grain is not identical to the sperm of pollen-producing plants but instead upon maturation contains the haploid nuclei that will serve to fertilize the egg, that is, the sperm nuclei. This gametophyte generation is greatly diminished and indeed its smallness aids in its function in aerial dissemination.

Pollen is produced by the male portion of flowers, that is, the stamen, and in conifers by what are known as male cones.