Question

differentiate between protonema and prothallus

Answer 1

Protonema is the first stage in the life cycle of a moss, developing directly from the spore. It consists of creeping, green, branched, and often filamentous structures.

Prothallus is the gametophyte of pteridophytes like fern that bears sex organs and produces gametes.
Prothallus
Protonema
It is the gametophyte of pterydophytes like fern.
It is the first stage of development in moss plants.
It has a heart like shape with numerous rhizoids and sex organs antheridium (male) and archegonium (female).
It is a thread like chain of cells.
It is formed from already germinated spore.
It is formed directly by the germination of spores.
Prothallus develops further to give rise to sperms and ova.

Answer 2

1.Protonema is filamentous leafy green colored structure whereas prothallus is a flat green heart shaped structure.
2.Protonema is formed as a result of the germination of the spores whereas prothallus is formed from an already germinated spores.
3.Protonema is the first stage of development in moss like plants whereas prothallus is the gametophyte of fern like pteridophytes.
4.Protonema develops into a leafy gametophore whereas prothallus develops to give rise to sex organs.