In Phycomycetes sexual reproduction occurs by-

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding Phycomycetes**: Phycomycetes, also known as the lower fungi, are characterized by their simple structure, often lacking septa in their hyphae, which results in a coenocytic (multinucleated) condition.

2. **Reproductive Methods**: Phycomycetes can reproduce both asexually and sexually. The question focuses on sexual reproduction.

3. **Types of Sexual Reproduction**: In Phycomycetes, sexual reproduction occurs through the fusion of gametes. There are three main types of sexual reproduction based on the morphology of the gametes:
- **Isogamous**: Both gametes are morphologically similar.
- **Anisogamous**: The gametes are different in size and shape, with one being larger (female) and the other smaller (male).
- **Oogamous**: This is a specific type of anisogamous reproduction where the female gamete is large and non-motile (egg), while the male gamete is small and motile (sperm).

4. **Conclusion**: Therefore, in Phycomycetes, sexual reproduction can occur through isogamous, anisogamous, or oogamous methods. The most common forms of sexual reproduction are isogamous and oogamous.

**Final Answer**: In Phycomycetes, sexual reproduction occurs by isogamous, anisogamous, and oogamous methods.

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