Sexual reproduction is of isogamous, anisogamous and oogamous they in :

Options

A. Chlorophyceae , Rhodophyceae and phaeophyceae
B. Rhodophyceae and phaeophyceae
C. Chlorophyceae , phaeophyceae
D. Chlorophyceae , Rhodophyceae

Answer

To solve the question regarding the types of sexual reproduction (isogamous, anisogamous, and oogamous) in different classes of algae, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Sexual Reproduction**:
- **Isogamous**: In this type, the gametes that fuse are of similar size and shape.
- **Anisogamous**: In this type, the gametes are of different sizes; one is larger (female) and the other is smaller (male).
- **Oogamous**: This is a specific form of anisogamy where the female gamete (ovum) is large and non-motile, while the male gamete (sperm) is small and motile.

2. **Identify the Classes of Algae**:
- **Chlorophyceae**: This class includes green algae, which can exhibit all three types of sexual reproduction: isogamous, anisogamous, and oogamous.
- **Rhodophyceae**: This class includes red algae, which primarily exhibit eugamous reproduction (a form of oogamy).
- **Pheophyceae**: This class includes brown algae, which can also exhibit isogamous, anisogamous, and oogamous types of reproduction.

3. **Analyze the Options**:
- **Option 1**: Chlorophyceae, Rhodophyceae, and Pheophyceae - Incorrect because Rhodophyceae does not exhibit all three types.
- **Option 2**: Rhodophyceae and Pheophyceae - Incorrect for the same reason as above.
- **Option 3**: Chlorophyceae and Pheophyceae - Correct as both classes exhibit isogamous, anisogamous, and oogamous types.
- **Option 4**: Chlorophyceae and Rhodophyceae - Incorrect because Rhodophyceae does not exhibit all three types.

4. **Conclusion**:
The correct answer is **Option 3: Chlorophyceae and Pheophyceae**.