Draw well labelled diagram of
A. Transverse section of anther.Microsporogenesis and formation of pollen grains.
1. Every cell of the sporogenous tissue is a potential pollen mother cell (PMC) and can give rise to microspore tetrad/ pollen grains.
2. But some of them forego this potential and others become differentiated into the pollen mother cells or microspore mother cells.
3. Each microspore mother cell undergoes meiosis to form a cluster of four haploid cells, called microspore tetrad.
Microsporogenesis.
4. As the anther matures, the microspores dissociate from the tetrad and develop into pollen grains.
5. The tetrad may be tetrahedral, isobilateral, T-shaped, L-shaped and linear.
6. The nucleus of the microspore undergoes mitosis to form large vegetative cell and a small spindle-shaped generative cell, that floats in the cytoplasm of the vegetative cell.