Question

3.A) What are the three main parts of the moss gametophyte?

3. B)What are the structures that are responsible for asexual reproduction in Marchantia? Describe these structures and explain how they function in asexual reproduction.

Answer 1

3A.

The three main parts of moss gametophytes are divided into leaves, main axis or stem and rhizoids.
Rhizoids :- Moss does not have roots but it contains are root like structures called rhizoids. The upright, slender axes which bears spirally arranged leaves are attached to the soil via these rhizoids. They are present beneath the soil.
Gametophyte :- it is haploid and the predominant stages which consists of main axis, leaves, mostly green in colour. It is the base of the moss. The leaves carry out photosynthesis.
It is interesting to note that the gametophytes has two stages 1. protonema and 2. leafy stage which gives its structure to it. First stage develop from the spores whereas second stage develop from the secondary protonema.
Sporophyte :- It consist of capsule and slender seta but no leaves. The capsule is sporangia which produces spores.

3B.

The structures responsible for asexual reproduction in Marchantia is gammae. These gammae develops into gamma cup which are located on the thallus. the gamma is a small packet of tissues The gamma detaches from the body and undergo germination which leads to the formation of new Marchantia.
The sexual reproduction is carried out through archegoniophore and antheridiophore.