Pollen grain is made up of two cells - vegetative and generative cell.
Vegetative cell is non-reproductive, and it forms the pollen tube once the pollen settles on the stigma of a flower. It is larger compared to the generative cell. And the vegetative cell is surrounded by a thin, delicate wall known as intine. Generative cell is the smaller cell which resides inside the pollen grain. It is reproductive, and it divides by mitosis and produces two male gametes or two sperm cells. A thin wall known as intine separates the generative cell.

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