Microspores vs Megaspores

Microspores and megaspores are sexual spores produced by vascular plants (some Pteridophytes and all Gymnosperms and Angiosperms) for sexual reproduction. Both microspores and megaspores on germination produce the respective gametophytic generations. The gametophytes on maturation produce sex organs and gametes to establish the fertilization and thus to complete the life cycle.

The production of different types of spores with different functions and sexuality is called Heterospory. The heterosporous condition was first evolved in Pteridophytes and it is considered as the prerequisite for seed habitat.

Learn more: Heterospory and Seed Habitat

The present post discusses the similarities and differences between microspores and megaspores with a comparison table.

Similarities between Microspore and Megaspore

Ø  Both microspores and megaspores are sexual spores.

Ø  Both are produced by the diploid sporophytic plants.

Ø  Both are haploid spores produced after reduction division of spore mother cells.

Ø  Both spores are produced in specialized structures called sporangium.

Difference between Microspore and Megaspore

Sl. No,	Microspores	Megaspores
1	Microspores are small sized spores.	Megaspores are comparatively large sized spores.
2	Microspores are produced in large numbers.	Megaspores are produced in limited numbers (usually 1, sometimes 4)
3	Microspores are produced inside the microsporangium.	Megaspores are produced inside the megasporangium.
4	Microsporangium is developed on microsporophyll.	Megasporangium is developed on megasporophyll.
5	Microspores are male spores	Megaspores are females pores
6	Microspore is the first cell of male gametophytic generation.	Megaspore is the first cell of female gametophytic generation.
7	Microspores are always liberated out from the sporophyte plant.	Megaspores are usually retained in the sporophyte plant (in Gymnosperms and Angiosperms).
8	Microspores on germination produce male gametophyte.	Megaspores on germination produce female gametophyte.
9	Male gametophyte develops antheridium with antherozoids.	Female gametophyte develops archegonium with egg.
10	Microspores are also called pollen grains in Gymnosperms and Angiosperms.	Megaspores are also called as Embryosac in Gymnosperms and Angiosperms

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