What is heterospory ? Briefly comment on its significances. Give two example.

Explanation

Heterospory is the occurrence of two typesof spores, namely microspores and megaspores, that give rise to male and female gametophytes respectively.
Importance : Heterospory has lead to seed habit in plants through.
i. Reduction in size of gametophytes.
ii. Dependence of gametophyte for nourishment on sporohyte
iii. Retention of female gametophyte in megasporangium.
Example : Salvinia, Selaginella.