In chlorophyceae, sexual reproduction occurs by

Options

A. Isogamy and anisogamy
B. Isogamy, anisogamy and oogamy
C. Oogamy only
D. Anisogamy and oogamy.

Answer

**Step-by-Step Solution:**

1. **Understanding Chlorophyceae**:
- Chlorophyceae is a class of green algae known for their diverse reproductive strategies.

2. **Types of Sexual Reproduction**:
- Sexual reproduction in Chlorophyceae can occur through three main types: isogamy, anisogamy, and oogamy.

3. **Isogamy**:
- Isogamy involves the fusion of gametes that are morphologically similar or identical. This means that both gametes look alike and are of the same size.

4. **Anisogamy**:
- Anisogamy refers to the fusion of dissimilar or non-identical gametes. In this case, the gametes differ in size and/or motility.

5. **Oogamy**:
- Oogamy is a type of reproduction where there is a large non-motile female gamete (egg) and a smaller motile male gamete (sperm). This is a common reproductive strategy in many organisms, including some green algae.

6. **Conclusion**:
- In Chlorophyceae, all three types of sexual reproduction (isogamy, anisogamy, and oogamy) are present. Therefore, the correct answer is that sexual reproduction occurs by all three methods.

**Final Answer**: Sexual reproduction in Chlorophyceae occurs by isogamy, anisogamy, and oogamy.

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