Botany lecture notes

Difference between Microspores and Megaspores: Comparison Table

microspores vs megaspores

Microspores vs Megaspores
(Similarities and Differences between Microspores and 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 Microspores and Megaspores

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.

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Botany lecture notes

Heterospory and Seed Habitat in Pteridophytes (Short Notes)

Significance of Heterospory

Heterospory and Seed Habitat
(Origin of Seeds and Seed Habitat in Vascular Plants from Heterospory)

Heterospory is the production of two or more types of spores

Heterospory is a condition of the production of more than one type (usually two) of spores in a single plant. These two types of spore differ in their formation, structure and most importantly its functions and sexuality. In Pteridophytes, these two spores are called as Microspores and Megaspores.

(1). Microspores:

Microspores are small sized spores produced in large numbers inside the microsporangium. They are male spores which on germination produce male gametophyte.

(2). Megaspores:

Megaspores are comparatively large spores produced in limited numbers (1 to 4) inside the megasporangium. They are female spores which on germination produce the female gametophyte.

Learn more: Difference between Microspores and Megaspores

The production of two types of spores with different sexuality was first evolved in Pteridophytes. Even though, the condition of heterospory is now represented only by eight living species of Pteridophytes, they are Selaginella, Isoetus, Marsilea, Salvinia, Azolla, Pilularia, Regnellidium and Platyzoma.

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