In chlorophyceae , the mode of sexual reproduction is

Options

A. Isogamy
B. Anisogamy
C. Oogamy
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Chlorophyceae**: Chlorophyceae, commonly known as green algae, are a group of photosynthetic organisms that contain chlorophyll. They can exist as unicellular, colonial, or filamentous forms.

2. **Types of Reproduction**: In Chlorophyceae, sexual reproduction can occur through three different modes: isogamy, anisogamy, and oogamy.

3. **Isogamy**: In isogamy, the gametes involved in reproduction are of the same size and shape. There is no differentiation between male and female gametes.

4. **Anisogamy**: In anisogamy, the gametes are of different sizes and shapes. Typically, one gamete is larger (often referred to as the female gamete) and the other is smaller (the male gamete).

5. **Oogamy**: Oogamy is a form of sexual reproduction where there is a distinct difference between the gametes. The female gamete is larger and non-motile, while the male gamete is smaller and motile (sperm).

6. **Conclusion**: Since Chlorophyceae can reproduce sexually through all three methods (isogamy, anisogamy, and oogamy), the correct answer to the question is "all of these."

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