Name the filamentous structure which appears in mosses due to germination of spore.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the filamentous structure that appears in mosses due to the germination of spores.

2. **Identifying the Structure**: In mosses, when spores germinate, they develop into a structure known as the protonema.

3. **Describing Protonema**: The protonema is a filamentous structure that represents an early stage in the life cycle of mosses. It is crucial for the development of the gametophytic stage, where gametes are produced.

4. **Haploid Nature**: The protonema is haploid (N), meaning it contains a single set of chromosomes. This is significant because it relates to the reproductive cycle of mosses.

5. **Function of Protonema**: The protonema helps in the formation of gametes (male and female) and ensures that the spore formation is viable, facilitating the life cycle of the moss.

6. **Conclusion**: Therefore, the answer to the question is "Protonema."

**Final Answer**: Protonema

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