Rarely among angiosperms,the pollen grains influence the endosperm. This is called as:

External fertilization is mostly observed in organisms that.....

Indicate the stages where meiosis and mitosis occur $(1, 2$ or $3)$ in the flow chart: Megaspore mother cell $\xrightarrow{1}$ Megaspores $\xrightarrow{2}$ Embryo sac $\xrightarrow{3}$ Egg.

Identify the ploidy of the following cells: Germ cell,Male gamete,Microspore mother cell,Microspore,Tube cell.

Flowering plants are more successful than other members of the plant world because

How many meiotic divisions are required to produce the pollen grains necessary for the formation of $800$ wheat seeds?