What is a $Pollen-embryo$?

Give the differences between Microsporangium and Megasporangium.

Select the correct option for the following statements:
$(i)$ In the embryo sac of angiosperms,the synergids and antipodals degenerate / do not degenerate after fertilization.
$(ii)$ In the leaves of dicotyledonous plants,parallel / reticulate venation is observed.

How many meiotic divisions are required to produce $64$ pollen grains?

Which of the following organisms reproduces only once in its lifetime?

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