After the seedling begins to photosynthesise, the cotyledons

Options

A. degenerate and fall off
B. become phloem tissue
C. change into root tissue
D. change into foliage leaves

Answer

**Step-by-Step Solution:**

1. **Understanding Cotyledons**: Cotyledons are the first leaves that develop from the seed during germination. They are also referred to as embryonic leaves.

2. **Function of Cotyledons**: Initially, cotyledons serve an important role in providing nutrients to the seedling. Since the seedling does not have true leaves at this stage, it relies on the stored food in the cotyledons for its growth and development.

3. **Initiation of Photosynthesis**: Once the seedling develops true leaves and begins the process of photosynthesis, it can produce its own food using sunlight, carbon dioxide, and water.

4. **Decline in Need for Cotyledons**: After the seedling starts photosynthesizing, the reliance on cotyledons for sustenance diminishes. The plant can now generate its own energy and nutrients.

5. **Degeneration of Cotyledons**: As the plant becomes self-sufficient through photosynthesis, the cotyledons lose their function and eventually degenerate. They may also fall off as they are no longer needed.

6. **Conclusion**: Therefore, after the seedling begins to photosynthesize, the cotyledons degenerate and may fall off since the plant can now sustain itself.

**Final Answer**: After the seedling begins to photosynthesize, the cotyledons degenerate and may fall off.

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