ABSTRACT
Pollen is considered as the male gamete in flowering plants or angiosperms and gymnosperms through which genetic information is transmitted to the offspring. To the naked eye pollen grains appear mainly in the form of a yellow or cream coloured powder, which look alike, but they are quite different in their wall pattern. The pollen tube acts as a channel of transport for the sperm cells to the embryo sac of the ovule to achieve fertilization. There is a tremendous variation in the size and shape of pollen grains. From the palynological point of view, the most important part in the flowers is the stamen or male reproductive organ consisting of pollen sacs or anthers borne on elongated stalks or filaments. Sporopollenin perhaps played a significant role in these organisms with regard to protection of protoplasm against ultraviolet radiation. The green algae are presumably responsible for the development of sporopollenin and its introduction into the armament of higher green plants.
