Explain the role of tapetum in the formation pollen-grain wall.
Tapetum is the innermost layer of the microsporangium. It provides nourishment to the developing pollen grains. During microsporogenesis, the cells of tapetum produce various enzymes, hormones, amino acids, and other nutritious material required for the development of pollen grains. It also produces the exine layer of the pollen grains, which is composed of the sporopollenin.
In an young anther the four rows of cells which later produce pollen are called
Diameter of pollen grain
At the time of pollination, how many cells are formed in the pollen grains
The microspore tetrad of angiosperm at the time of formation, are surrounded by a callose wall. Breakdown of this wall is brought about by the enzyme callase synthesized by the