What is the most appropriate term for a mature pollen grain?

Question

Quizplus · Accepted Answer

A mature pollen grain is the male gametophyte, which contains the sperm cells that will fertilize the female gametophyte. Megaspores and microspores are the precursor cells that give rise to female and male gametophytes, respectively. The female gametophyte is also known as the embryo sac, and is not the same as a mature pollen grain. Immature sporophyte refers to a developing plant embryo, and is not a term used to describe pollen.

What Is the Most Appropriate Term for a Mature Pollen