Asexual reproduction takes place by zoospores or by aplanospores in

Options

A. Colletotrium
B. Saccharomyces
C. Rhizopus
D. Alternaria

Answer

To solve the question regarding which organism reproduces asexually by zoospores or aplanospores, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Asexual Reproduction**: Asexual reproduction involves the production of offspring without the fusion of gametes. In this context, we are focusing on two types of asexual spores: zoospores and aplanospores.
- **Zoospores**: These are motile spores that can move in water.
- **Aplanospores**: These are non-motile spores that do not have the ability to move independently.

2. **Identify the Groups of Fungi**: The question lists four options, and we need to identify which of these fungi reproduce asexually using zoospores or aplanospores.
- **Colletotrichum**: This fungus belongs to the group Deuteromycetes, which typically reproduce asexually by conidia, not zoospores or aplanospores.
- **Saccharomyces**: This yeast is a member of Ascomycetes and reproduces asexually by budding or through the formation of ascospores, not by zoospores or aplanospores.
- **Rhizopus**: This is a member of Phycomycetes, which is known to reproduce asexually by both zoospores and aplanospores.
- **Alternaria**: This fungus is also a member of Deuteromycetes and reproduces by conidia.

3. **Evaluate the Options**: Based on the characteristics of each organism:
- **Colletotrichum**: Incorrect (Deuteromycetes)
- **Saccharomyces**: Incorrect (Ascomycetes)
- **Rhizopus**: Correct (Phycomycetes)
- **Alternaria**: Incorrect (Deuteromycetes)

4. **Conclusion**: The only organism from the given options that reproduces asexually by zoospores or aplanospores is **Rhizopus**.

### Final Answer:
The correct answer is **Option 3: Rhizopus**.

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