Question

Role of generative cell and vegetative cells in pollen

Answer 1

When pollen grains travel from stigma to style, vegetative cell ruptures and disintegrates. Generative cell travels to the ovary for the formation of zygote in which triple fusion takes place for the nourishment of the embryo.

Answer 2

Answer

• The pollen grains is the first cell of male gametophyte.

• The development of male gametophyte begins even before the pollen grains are shed from the anther soon after the formation of pollen grains.

• Its nucleus divides into a large vegetative cell and a small generative cell.

• Vegetative cell is called tube cell and its nucleus is called tube nucleus.

• The generative cell flots in the tube cell.

• The entire structure of pollen grain is referred to as male gametophyte.

• In most of angiosperms the pollen grains are liberated at the two celled stage.

• After reaching stigma, the intine grows out through a germ pore into a slender pollen tub.

• The generative tube divides into two male gametes.

• Process of development of male gametophyte from pollen grain is called microgametogenesis.