Comment on the lifecycle and nature of a fern prothallus.

Life Cycle:

• Fern shows diplo-haplontic life cycle.


• Diploid sporophyte represents the dominant, independent, photosynthetic plant body.


• The sporophyte bears sporangia which produces spores by meiosis.


• These spores germinate to form free living prothallus which represents a gametophyte.


• Sexual reproduction: syngamy results in formation of diploid zygote. Zygote germinates into a diploid sporophyte.


Prothallus:


• It represents the gametophytic phase.


• Multicellular, independent, green, photosynthetic thallus.


• It needs damp and shady places.


• Bears sex organs, rhizoids and food laden parenchymatous cells.


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