Cotyledons are

Options

A. Modified roots
B. Embryonic leaves
C. Known as primary endosperm nucleus
D. Present in gymnospermic seeds only

Answer

**Step-by-Step Solution:**

1. **Definition of Cotyledons**: Cotyledons are the first leaves that appear from a germinating seed. They are part of the embryo within the seed.

2. **Role in Seed Structure**: In the structure of a seed, cotyledons are located alongside the plumule (the shoot) and radicle (the root). They are essential for the seed's development.

3. **Nutritional Function**: Cotyledons serve as the primary source of nutrition for the developing plant during germination. They store food reserves that are utilized by the embryo until it can produce its own food through photosynthesis.

4. **Presence in Plant Groups**: Cotyledons are found in both gymnosperms and angiosperms. They are not exclusive to gymnospermic seeds, as they also play a crucial role in angiospermic seeds.

5. **Misconceptions**: It is important to clarify that cotyledons are not modified roots or embryonic leaves. They are specialized structures that serve a specific function in the early stages of a plant's life.

6. **Conclusion**: In summary, cotyledons are essential parts of the seed that provide nutrients to the growing plant and are present in both major groups of seed plants.

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