In ectoderm of Hydra, bulk of cells are

Options

A. Musculo-epithelial
B. Interstitial
C. Nematoblasts
D. Germ cells.

Answer

**Step-by-Step Solution:**

1. **Understanding Hydra's Structure**: Hydra is a simple organism that has two primary germ layers: ectoderm and endoderm. The ectoderm is the outer layer, while the endoderm is the inner layer.

2. **Identifying the Ectoderm**: The ectoderm in Hydra is primarily responsible for forming the epidermis. This layer includes various types of cells that contribute to the overall function of the organism.

3. **Musculoepithelial Cells**: The bulk of cells found in the ectoderm of Hydra are known as musculoepithelial cells. These cells are a combination of muscle and epithelial cells. They play a crucial role in the contraction and movement of Hydra.

4. **Function of Musculoepithelial Cells**: These musculoepithelial cells allow Hydra to contract, which is essential for its movement and feeding. They provide both structural support and the ability to move.

5. **Conclusion**: Therefore, the correct answer to the question "In ectoderm of Hydra, bulk of cells are" is that they are musculoepithelial cells.

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