Verified Answer :

Prothallus represents a gametophyte in the life
cycle of fern.

 

A prothallium, or prothallus (from Latin pro = forwards and Greek θαλλος
(thallos) = twig) is usually the gametophyte stage in the life of a fern or
other pteridophyte. Occasionally the term is also used to describe the young
gametophyte of a liverwort or peat moss as well.

 

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