In three filaments are involved in lateral conjugation in Spirogyra, zygospores will be found in

Options

A. All the three filaments
B. Only the middle filament
C. Lateral filaments
D. Either B or C.

Answer

To solve the question regarding the presence of zygospores in Spirogyra during lateral conjugation involving three filaments, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Conjugation in Spirogyra**:
- Spirogyra reproduces sexually through a process called conjugation, which can occur in two forms: lateral conjugation and scleriform conjugation.

2. **Identifying Lateral Conjugation**:
- In lateral conjugation, the process occurs within a single filament. Adjacent cells on the same filament produce gametes that meet and develop within a short curved conjugation tube.

3. **Analyzing the Role of Three Filaments**:
- The question specifies that three filaments are involved in lateral conjugation. However, in lateral conjugation, the interaction primarily occurs within one filament.

4. **Locating Zygospores**:
- Zygospores are formed when the gametes fuse. In the case of lateral conjugation, since the gametes are produced by adjacent cells on the same filament, the zygospores will be found in the filament where the conjugation occurs.

5. **Considering the Options**:
- The options provided are:
- A) All three filaments
- B) Only the middle filament
- C) Lateral filaments
- D) Either B or C
- Since lateral conjugation occurs within one filament, the zygospores will be found in the filament where the conjugation occurs, which could be either the middle or lateral filaments.

6. **Conclusion**:
- Therefore, the correct answer is that zygospores will be found in either the middle filament or the lateral filaments, which corresponds to option D.

### Final Answer:
**Zygospores will be found in either the middle filament or the lateral filaments (Option D).**

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