Question

Which is not a part of the moss capsule?
A.Peristome
B.Protonema
C.Theca from operculum
D.Annulus

Answer 1

Hint:Mosses are a group of flowerless plants belonging to the Bryophyta division, which grow as clumps or mats in damp locations that do not possess any developed vasculature. These organisms reproduce utilizing spore formation. The sporophyte consists of a stalk called seta and caped by the operculum. The mouth of the capsule is lined with projections called peristome. As the capsule cleaves and releases the spores, under favorable conditions germinate to form protonema.

Complete answer:Mosses are a poorly developed organism which belongs to the taxonomic division of Bryophyta. These organisms grow on damp surfaces such as tree barks, wet rocks, etc.
This organism does not possess any special vasculature and is mostly composed of leaves which are only one thick cell attached to a stem-like structure. Due to the poor development of this organism, it does not possess any complex reproductive capabilities and requires the use of sporophytes which produce and disperse spores through the wind.
The sporophytes are diploid multicellular cells that produce spores. In the case of moss, the spores are produced by the sporophyte through meiosis. During the sporophyte development process, it is covered by a capsule. This capsule at the end of sporophyte development sheds and release the spores into the air.
During the development stage, the capsule is attached to a stalk called the seta and is enveloped by a cap called the operculum. The mouth of the entire capsule is aligned by single or multiple rings of hair or teeth-like structures called the peristome. Its main function is to aid in the dispersion of the spores.
Once the spores are produced within the capsule (theca), the capsule degenerates and dries off, leaving the mouth (operculum) open. With the aid of the peristome, the spores are dispersed into the air, and under favorable conditions, they grow a filamentous thread-like structure called the protonema which then forms the gametophores. These gametophores then form sporophytes of their own and begin their own cycle of spore formation.
Therefore, the correct option is B, protonema.

Note:Mosses are non-flowering, poorly developed species belonging to the Bryophyta division.
They reproduce via spores, which are formed within the sporophytes of the plant.
The sporophytes produce spores within a capsule, which consists of the seta, theca, operculum, peristome, and apophysis. The seta is the stalk, the apophysis the portion connecting the capsule to the stalk, the theca is where the spore is produced, the operculum is the mouth of the capsule which is surrounded by teeth like structure called the peristome.
Protonema is the filamentous growth of spores into a long fiber-like structure that forms the mature moss plant.