Question

Protonema occurs in the life cycle of

• A. Riccia
• B. Funaria
• C. Anthoceros
• D. Spirogya.

Answer 1

The Correct Option is B

The question asks about the life cycle of plants and specifically where the "protonema" occurs. Protonema is a stage in the life cycle of bryophytes, which are non-vascular plants. It is most commonly associated with mosses.

Let's evaluate the options to identify which plant has the protonema stage in its life cycle:

1. Riccia: This is a genus of liverworts, which do not exhibit the protonema stage. Instead, they directly produce gametophytes from spores.
2. Funaria: Funaria is a well-known moss. Mosses characteristically show a dominant gametophyte stage which begins with the formation of protonema, a filamentous structure similar to green algae. This is where the answer lies.
3. Anthoceros: This is a genus of hornworts, which, like liverworts, also do not exhibit a clear protonema stage like mosses do.
4. Spirogya: Spirogyra is a genus of filamentous green algae and does not belong to bryophytes, hence, does not have a protonema stage.

Conclusion: The correct answer is Funaria, as it is a moss and the protonema stage is prominent in the life cycle of mosses.

To explore this concept further, in the life cycle of mosses like Funaria, after the spore germinates, it forms a \text{protonema}, which is a filamentous stage. This structure gives rise to the leafy gametophyte, which is the dominant stage in the life cycle of mosses.