Zygospores formed by the conjugation of coenogametangia are

Options

A. thin walled and blue green
B. thick walled and black
C. thick walled and green
D. thin walled and bluish.

Answer

To answer the question about the type of zygospores formed by the conjugation of coenogametangia, we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Gametangia**:
- Gametangia are specialized organs or cells in fungi where gametes are produced. In the case of coenogametangia, they contain a dense cytoplasm and multiple nuclei.

2. **Formation of Coenogametangia**:
- Coenogametangia are multinucleate structures that arise from the fusion of gametangia. When these structures are formed, the common wall between them dissolves.

3. **Fusion Process**:
- The two coenogametangia fuse together, leading to the formation of a fusion cell known as a synozygote. This process involves two key events:
- **Plasmogamy**: The fusion of the cytoplasm from the two gametangia.
- **Karyogamy**: The fusion of the nuclei from both gametangia.

4. **Formation of Zygospore**:
- After the fusion, a thick two-layered wall develops around the protoplast of the fusion cell, resulting in the formation of a zygospore. This zygospore is a diploid cell.

5. **Characteristics of Zygospores**:
- The zygospore has a thick wall that is composed of two layers:
- **Exospore**: The outer layer, which is dark-colored and deeply sculptured.
- **Endospore**: The inner layer, which is smooth.

6. **Conclusion**:
- Therefore, the zygospores formed by the conjugation of coenogametangia are characterized as thick-walled and dark-colored (often described as black).

### Final Answer:
Zygospores formed by the conjugation of coenogametangia are thick-walled and dark-colored.

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