Question

Two mark Questions:
Name the organic materials the exine and intine of an angiosperm pollen grains are made up of. Explain the role of exine.

Answer 1

The exine layer is made up of sporopollenin, which is one of the most resistant substances found in nature. The intine layer is made up of cellulose and pectin materials.

Exine plays an important role in:

(1) It protects gametophytes in harsh environments and serves as a barrier against various physical and chemical factors and biological pathogens.

(2) It helps in pollen dispersal and cross-pollination in some species.

(3) It enables stigma cells to capture the most appropriate pollen grains by providing species-specific factors for pollen-stigma recognition and adhesion.