Algae reproducing by both isogamy and anisogamy is

Options

A. Fucus.
B. Volvox.
C. Sprirogyra
D. None of these

Answer

To solve the question regarding algae that reproduce by both isogamy and anisogamy, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Reproduction**:
- **Isogamy**: This is a type of sexual reproduction where the gametes are of the same size and shape. They can be flagellated or non-flagellated.
- **Anisogamy**: This type involves gametes that are of different sizes and shapes. Typically, one gamete is larger (often non-motile) and the other is smaller (often motile).

2. **Identify Examples of Isogamy**:
- In algae, **Chlamydomonas** is a well-known example where isogamous reproduction occurs. The gametes produced are similar in size and can be flagellated.

3. **Identify Examples of Anisogamy**:
- Some species of **Chlamydomonas** also exhibit anisogamy, where the gametes differ in size. This shows that Chlamydomonas can reproduce in both ways.

4. **Consider Other Algal Examples**:
- **Spirogyra** is another example of isogamous reproduction, but it does not reproduce via anisogamy.
- **Volvox** and **Fucus** are examples of oogamous reproduction, which is different from both isogamy and anisogamy.

5. **Conclusion**:
- Since Chlamydomonas is the only algae that reproduces by both isogamy and anisogamy, it is the correct answer to the question.

### Final Answer:
The algae reproducing by both isogamy and anisogamy is **Chlamydomonas**.

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