Explain the gametophyte of Marchantia?

Explanation

The plant body of Marchantia is a gametophyte. It is prostrate, dorsiventral and dichotomously branched. The thallus on the dorsal surface possess conspicuous median midrib which is marked by a shallow groove on dorsal surface. The dorsal surface appears to have rhomboidal or polygonal diamond shaped areas which indicate the outline of the underlying air chambers of the thallus.

(a) Thallus with antheridiophore
(b) Thallus with archegoniophore
1. The dorsal surface also shows crescent shaped structures called gemma cups which contain vegetative reproductive structures called gemmae.
2. The apical notch bears an apical cell which helps in the growth of the thallus.
3. The ventral surface the thallus bears multicellular scales and rhizoids which help in fixation and absorption of water and minerals.
4. The rhizoids are of two types namely smooth walled or pegged ( tuberculate ) type.
5. On maturation the thallus bears erect antheriophores and archegoniophores.