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Question
A Prothallus is ______.
Options
A structure in pteridophytes formed before the thallus develops
A sporophytic free living structure formed in pteridophytes
A gametophyte free living structure formed in pteridophytes
A primitive structure formed after fertilization in pteridophytes
Solution
A Prothallus is a gametophyte free living structure formed in pteridophytes.
Explanation:
In pteridophytes, meiosis or R/D occurs at the time of spore formation. The spores germinate to give rise to inconspicuous, small but multicellular, free-living, mostly photosynthetic thalloid gametophytes called prothallus. Prothallus represents the gametophytic phase in pteridophytes.
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