Which green algae shows only oogamous type sexual reproduction ?

Options

A. Ulothrix
B. Volvox
C. Spirogyra
D. Chlamydomonas

Answer

To solve the question "Which green algae shows only oogamous type sexual reproduction?" we can follow these steps:

### Step 1: Understand the Types of Sexual Reproduction in Algae
- Sexual reproduction in algae can be classified into three main types: isogamous, anisogamous, and oogamous.
- **Isogamous**: This type involves the fusion of two gametes that are similar in size and often flagellated. Examples include Chlamydomonas and Spirogyra.
- **Anisogamous**: This type involves the fusion of two gametes that are dissimilar in size. One gamete is larger and non-motile (female), while the other is smaller and motile (male).
- **Oogamous**: This is a specific type of anisogamous reproduction where the female gamete is large and non-motile, and the male gamete is smaller and motile.

### Step 2: Analyze the Given Options
- **Eulothrix**: Exhibits isogamous reproduction.
- **Volvox**: Exhibits oogamous reproduction.
- **Spirogyra**: Exhibits isogamous reproduction.
- **Chlamydomonas**: Exhibits isogamous reproduction (with some species showing anisogamous).

### Step 3: Identify the Correct Answer
- From the analysis, we find that **Volvox** is the green alga that shows only oogamous type sexual reproduction.

### Conclusion
The answer to the question is **Volvox**.

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