Which of the following structure is not related to the life cycle of Funaria ?

Options

A. Protonema
B. Spore
C. Prothallus
D. Antheridia

Answer

To solve the question of which structure is not related to the life cycle of Funaria, we can analyze the given options and their relevance to Funaria's life cycle step by step.

### Step-by-Step Solution:

1. **Understanding Funaria**: Funaria is a type of moss and belongs to the group of plants known as bryophytes. Bryophytes are characterized by their life cycle which includes both gametophyte and sporophyte stages.

**Hint**: Recall that Funaria is a moss and part of the bryophyte group.

2. **Identifying the Structures**: The options provided are:
- Protonema
- Spore
- Prothallus
- Antheridia

**Hint**: List out what each structure is and its role in the life cycle of mosses.

3. **Protonema**: This is the first stage of the moss life cycle that develops from the spore. It is a filamentous structure that eventually gives rise to the leafy gametophyte.

**Hint**: Protonema is crucial for the development of the moss gametophyte.

4. **Spore**: Spores are the reproductive units of mosses that germinate to form the protonema. They are essential for the reproduction of Funaria.

**Hint**: Spores are the starting point of the moss life cycle.

5. **Antheridia**: These are the male sex organs found on the gametophyte of Funaria. They produce sperm necessary for fertilization.

**Hint**: Antheridia are directly involved in the sexual reproduction of Funaria.

6. **Prothallus**: This structure is actually the gametophyte of pteridophytes (ferns), not bryophytes. It is a heart-shaped structure that produces gametes but is not part of the life cycle of Funaria.

**Hint**: Prothallus is associated with ferns, not mosses.

7. **Conclusion**: The structure that is not related to the life cycle of Funaria is **Prothallus**.

### Final Answer:
**Prothallus** is not related to the life cycle of Funaria.