Name the male gamete in a flower. Explain its structure.

Explanation

a. Pollen grains are the mature microspore. The wall of the pollen grain is made up of outer exine and an inner intine.
b. The exine is outerhard coat due to the prescnce of sporollenin, whereas intine is made up of cellulose and pectin.
c. The pollen grain has germpore through which the pollen tube germinate.
d. Enclosed within the wall are two unequal cells. The larger one is called the vegetative cell and the smaller one is called the generative cell.
e. The vegetative cell has abundant food reserve, a large irregularly shaped nucleus and a floating generative cell in its cytoplasm.
f. The generative cells produce two male gametes, which takes part in double fertilization.