If the cells of the root in a wheat plant have $42$ chromosomes,then the number of chromosomes in the cell of a pollen grain is:

What is required for the formation of microspores from a microspore mother cell?

The function of the innermost layer of the pollen sac,the tapetum,is:

$A$ typical angiosperm anther is:

$A$: Each cell of the sporogenous tissue is capable of giving rise to a microspore tetrad.
$R$: The most abundant type of microspore tetrad is the product of simultaneous cytokinesis.

In flowering plants,meiosis occurs at the time of: