POLLEN

A pollen grain is a highly reduced male gametophyte. Its main function is to germinate on a stigma and give rise to a pollen tube which takes the sperm nucleus down to the ovarial complex. A majority of pollen grains are spherical, and there is considerable variation in size.

Pollen analysis is concerned with the study of fossil assemblages of pollen grains and spores that have been isolated from sediments deposited in the recent past, or as far back as the Paleozoic era. Primary applications are to study vegetation and climate history.

Pollen durability makes it a suitable candidate for ecological studies. The outer layer, or exine, contains one of the most extra-ordinary resistant materials known in the organic world. The intine is the middle layer of the angiosperm pollen grain. It consists of cellulose, and is the extra-cytoplasmic part of the pollen grain that is not fossilized.

The pollen grains on this web page are shown in up to three views. The equatorial plane is the plane perpendicular to the axis of symmetry through the middle of the grain. The polar view is the top view of the grain. In some cases, a surface pattern is also shown. This is the texture, or roughness visible when magnifying through a pollen grain.

Faegri, Knut, Iversen, Johs. Textbook of Pollen Analysis. John Wiley & Sons.1989.