Question

Exine should be hard why and what is the function of germ pore?

Answer 1

Exine should be hard, because it protects pollen grains under adverse conditions.

Through germ pores, pollen tube comes out from pollen grain upon deposition on stigma of flower.

Hope it helps

Answer 2

$\tt\pink{\underline{Exine}}$

→ It age outer layer of pollen grain and very hard.

→ It age made up of sporopollenin in which is most resistance organic material present in nature .

→Sporopollenin is Resistance to high temperatures stronger acids and alkaline and also to enzyme .