Gymnosperms are called naked seed plants because they lack

Options

A. Cotyledons
B. Endosperm
C. Testa
D. Ovary wall.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Gymnosperms**: Gymnosperms are a group of seed-producing plants that include conifers, cycads, and ginkgo. They are characterized by their seeds being exposed rather than enclosed in a fruit.

2. **Meaning of 'Naked Seed'**: The term "naked seed" refers to the fact that the seeds of gymnosperms are not covered by an ovary wall. This is in contrast to angiosperms, where seeds are enclosed within a fruit.

3. **Analyzing the Options**:
- **Option A: Cotyledons**: Cotyledons are the first leaves that appear on a seedling. Gymnosperms do have cotyledons.
- **Option B: Endosperm**: Endosperm is the tissue that provides nourishment to the developing embryo. Gymnosperms can have endosperm.
- **Option C: Testa**: The testa is the seed coat. Gymnosperms do have a seed coat.
- **Option D: Ovary wall**: Gymnosperms lack an ovary wall, which is why their seeds are exposed.

4. **Conclusion**: Since gymnosperms do not have an ovary wall, their seeds are considered "naked." Therefore, the correct answer is option D: ovary wall.

**Final Answer**: D. Ovary wall

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