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 1: Understand the Types of Reproduction
- **Isogamous**: This type of reproduction involves gametes that are morphologically similar (same size and shape).
- **Anisogamous**: In this type, the gametes are of different sizes and shapes (one is larger, typically the female gamete).
- **Oogamous**: This is a form of anisogamy where there is a large non-motile egg (female) and a smaller motile sperm (male).

### Step 2: Identify the Classes of Algae
The question mentions three classes of algae:
1. **Chlorophyceae (Green Algae)**
2. **Rhodophyceae (Red Algae)**
3. **Pheophyceae (Brown Algae)**

### Step 3: Determine the Reproductive Types in Each Class
- **Chlorophyceae**: Exhibits all three types of reproduction (isogamous, anisogamous, and oogamous).
- **Rhodophyceae**: Primarily exhibits oogamous reproduction.
- **Pheophyceae**: Exhibits all three types of reproduction (isogamous, anisogamous, and oogamous).

### Step 4: Analyze the Options
Now, let’s evaluate the provided options:
1. **Chlorophyceae, Rhodophyceae, and Pheophyceae**: Incorrect, as Rhodophyceae only has oogamous reproduction.
2. **Rhodophyceae and Pheophyceae**: Incorrect, as Rhodophyceae does not have isogamous or anisogamous reproduction.
3. **Chlorophyceae and Pheophyceae**: Correct, as both classes exhibit all three types of reproduction.
4. **Chlorophyceae and Rhodophyceae**: Incorrect, as Rhodophyceae only has oogamous reproduction.

### Step 5: Conclusion
Based on the analysis, the correct answer is **Option 3: Chlorophyceae and Pheophyceae**.

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