In Hydra, gastric enzymes are secreted by

Options

A. Epithelioglandular cells
B. Endothelio-muscular cells
C. Epithelio-muscular cells
D. Endothelioglandular cells.

Answer

**Step-by-Step Solution:**

1. **Understanding Hydra's Body Structure**: Hydra has a simple body structure consisting of two main layers: the outer ectoderm and the inner endoderm. The ectoderm forms the outer epithelial layer, while the endoderm forms the gastrodermis.

2. **Identifying Cell Types**: In the ectoderm, we find various cell types, including epithelio-muscular cells, nidoblasts (stinging cells), germ cells, interstitial cells, sensory cells, and nerve cells. The gastrodermis, derived from the endoderm, contains gland cells, nutritive muscular cells, interstitial cells, sensory cells, and nerve cells.

3. **Focusing on Gastric Enzymes**: The question specifically asks about the secretion of gastric enzymes. In Hydra, these enzymes are crucial for digestion.

4. **Identifying the Correct Cells**: The cells responsible for the secretion of gastric enzymes are the gland cells found in the gastrodermis. These cells are also referred to as endothelial glandular cells.

5. **Conclusion**: Therefore, the correct answer to the question is that gastric enzymes in Hydra are secreted by the endothelial glandular cells.

**Final Answer**: Gastric enzymes in Hydra are secreted by endothelial glandular cells.

---