Question

Examine the given figure and select the correct options giving all the four parts(a, b, c, d) correctly identified.

A) A-Seta, B-Sporophyte, C-Protonema, D-Rhizoids
B) A- Antheridiophore, B-Male thallus, C-Globules, D-Roots
C) A-Archegoniophore, B-Female thallus, C-Bud, D-Foot
D) A-Archegoniophore, B-Female thallus, C-Gemma cup, D-Rhizoids

Answer 1

Hint: The given figure is of Marchantia which is a bryophyte. Bryophytes are known to be small plants that are non-vascular and do not produce flowers or seeds and instead reproduce by the formation of spores.

Complete answer:
Marchantia is composed of two layers- an upper photosynthetic layer and a lower layer that serves for storage. It consists of a thallus containing tiny structure known as Gemma cups used for asexual reproduction. Rhizoids are present on the ventral surface of the thallus which are unicellular. Marchantia is known to reproduce both sexually and asexually. Asexual reproduction occurs with the help of Gemma cups.

Asexual reproduction also takes place when older plant parts die and new survivor branches develop into new plants. Sexual reproduction takes place with the help of sperm from antheridium and ovum in the archegonium. The antheridia and archegonia are in turn borne on the antheridiophore and archegoniophore. On fertilization a sporophyte is formed that gives rise to spores. The parts of

Marchantia with labelling are given below.

So the correct option is D) A-archegoniophore, B-Female thallus, C-Gemma cup, D-Rhizoids

Note: Marchantia is found worldwide and requires moist soil and damp rocks for their growth. They are mostly found on river and pool banks, fens and dune slacks. It is also found in man made habitats such as gardens and greenhouses.