Explain the stages involved in the maturation of a microspore into a pollen grain.
The microspore comprises a dense cytoplasm and a bigger nucleus in the center. As the microspore develops the nucleus is shifted towards the side due to the production of vacuoles in the upper end of the cytoplasm. The mitotic division causes the nucleus to produce two nuclei which separate out into 2 cells; the lower generative cell and the upper bigger vegetative cell. A mature pollen grain normally has 2 cells.
