Consider the following plants :
yeast, Spirogyra, Bryophyllum, Rose, Fern, Sweet potato
Which of these plants is reproduced :
by fragmentation ?

Answer

To determine which of the listed plants reproduces by fragmentation, we can analyze each option based on their reproductive methods.

### Step-by-Step Solution:

1. **Understand Fragmentation**: Fragmentation is a form of asexual reproduction where an organism breaks into fragments, and each fragment can grow into a new individual.

2. **List the Plants**: The plants we need to consider are:
- Yeast
- Spirogyra
- Bryophyllum
- Rose
- Fern
- Sweet potato

3. **Analyze Each Plant**:
- **Yeast**: Yeast reproduces mainly by budding, which is not fragmentation.
- **Spirogyra**: Spirogyra is an algae that reproduces by fragmentation. When it matures, it can break into fragments, and each fragment can develop into a new organism.
- **Bryophyllum**: Bryophyllum reproduces through vegetative propagation, mainly through its leaves, not by fragmentation.
- **Rose**: Roses are typically propagated by cuttings, which is a form of vegetative reproduction, not fragmentation.
- **Fern**: Ferns reproduce through spores, not by fragmentation.
- **Sweet potato**: Sweet potatoes reproduce through tubers, which is also a form of vegetative reproduction.

4. **Conclusion**: The only plant from the list that reproduces by fragmentation is **Spirogyra**.

### Final Answer:
**Spirogyra** is the plant that reproduces by fragmentation.

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