Transport Mechanisms of Pollen — A Short Review

Pollination is a process typical of gymnosperms and angiosperms. Gymnosperm pollen grains are produced by the pollen sacs and land on the micropyle of the ovule, very close to the existing or future female gametophyte. Angiosperm pollen is produced by anthers and lands on the stigma, even as far as several centimeters from the female gametophyte contained in the ovary.