Testes/gonads are formed in Hydra from

Options

A. Interstitial cells
B. Epithelio-muscular cells
C. Nerve cells
D. All of above.

Answer

To answer the question "Testes/gonads are formed in Hydra from", we can follow these steps:

### Step 1: Understand the structure of Hydra
Hydra is a simple organism belonging to the phylum Cnidaria. It has various types of cells that perform different functions, including interstitial cells, epithelial muscular cells, and nerve cells.

**Hint:** Identify the types of cells present in Hydra and their functions.

### Step 2: Identify the role of interstitial cells
Interstitial cells in Hydra are responsible for producing gametes. These cells undergo repeated cell divisions to form the testes (male gonads) and ovaries (female gonads) in Hydra.

**Hint:** Focus on which cells are involved in reproduction.

### Step 3: Evaluate the other cell types
- **Epithelial muscular cells**: These cells provide protection and help in the movement of Hydra by contracting and shortening its body.
- **Nerve cells**: These form a nerve net that helps in transmitting impulses, allowing Hydra to respond to stimuli.

**Hint:** Consider the functions of epithelial muscular cells and nerve cells to see if they relate to gonad formation.

### Step 4: Analyze the options given
The options provided are:
1. Interstitial cells
2. Epithelial muscular cells
3. Nerve cells
4. All of the above

From our analysis, we see that only interstitial cells are responsible for the formation of testes and gonads.

**Hint:** Compare the functions of each cell type to determine which one is correct.

### Step 5: Conclusion
The correct answer to the question is that testes/gonads in Hydra are formed from **interstitial cells**.

**Final Answer:** Interstitial cells.