Question

In Funaria, the haploid structure is
A. Protonema
B. Capsule
C. Columella
D. Seta

Answer 1

Hint: The Funaria is considered to be a moss. It is also referred to as cord moss. They prefer to grow in moist places and are mostly found on crevices of rocks. A situation where the cells have only one set of chromosomes is termed as haploid. If we talk about the life cycle of Funaria, it is of haplo-diplontic type. They reproduce by producing spores and they lack a vascular system.

Complete answer:
The life cycle of Funaria has two generations; Gametophytic (n) and the Sporophytic (2n).
> Protonema- Its structure is such that it forms thread-like chains of cells in haploid phase. It happens due to germination of spores. During the growth process, a moss first grows as protonema. The gametophytic is the haploid generation which is depicted by protonema. This protonema produces spermatozoids and eggs in antheridium and archegonium respectively.

> Capsule- The very end part of sporophyte is the capsule. The function of a capsule is water conduction and providing nutrients to the capsule that is developing. It is not the haploid structure.

> Columella- It is the middle region consisting of parenchyma cells. It is found within the sporangium. It acts as a conducting tissue which is responsible for water and nutrients conduction which helps the growing sporophyte.

> Seta- It is a long stalk-like structure which has a capsule at its tip which is shaped like a pear.

Hence, the correct answer is option (A).

Additional information:
There are various methods for vegetative propagation in Funaria which include;
1) Fragmentation of primary protonema where loss of intercalary causes fragmentation in protonema which further gives rise to leafy gametophore.
2) By secondary protonema which develops from the cell of the injured part of the gametophyte.
3) By Bulbils which are also called tubers and they develop on rhizoids.
4) By Gemmae where its detachment leads to gametophyte where conditions are suitable.
5) Apospory where any somatic cell is capable of producing gametophyte despite no spore formation.

Note: In Funaria, the gametophyte which is the haploid, goes through vegetative propagation to form more gametophyte generations before the development of sporophyte.