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
- There are three main types of sexual reproduction in algae: isogamous, anisogamous, and oogamous.
- **Isogamous**: Gametes are of the same size and shape.
- **Anisogamous**: Gametes are of different sizes but both are motile.
- **Oogamous**: Involves a large, non-motile female gamete (egg) and a smaller, motile male gamete (sperm).

### Step 2: Analyze the Given Options
- The options provided are: Lautrec, Volvox, Pyrogyra, and Chlamydomonas.
- We need to identify which of these algae exhibit oogamous reproduction.

### Step 3: Review Each Alga
- **Lautrec**: Not commonly referenced in the context of sexual reproduction.
- **Volvox**: Known to reproduce sexually via oogamous reproduction, where the female gametes are larger and non-motile.
- **Pyrogyra**: Typically shows isogamous reproduction.
- **Chlamydomonas**: Generally exhibits isogamous or anisogamous reproduction.

### Step 4: Identify the Correct Answer
- From the analysis, **Volvox** is the green alga that shows only oogamous type sexual reproduction.

### Final Answer
The green algae that shows only oogamous type sexual reproduction is **Volvox**.

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