Gas gland occurs in

Options

A. Gorgonia
B. Physalis
C. Pennatula
D. Red Coral.

Answer

To answer the question "Gas gland occurs in," we will analyze the options provided and identify which organism possesses gas glands.

### Step-by-Step Solution:

1. **Understanding Gas Glands**:
- Gas glands are specialized structures found in certain marine organisms. They are responsible for the regulation of buoyancy by controlling the gas content within the organism.

2. **Analyzing the Options**:
- **Option 1: Gorgonia**:
- Gorgonia is known as soft coral. It does not have gas glands; instead, it has a flexible structure due to the absence of a hard calcium skeleton.

- **Option 2: Physalia (Man-of-war)**:
- Physalia, commonly known as the Portuguese man-of-war, is a colonial organism that has tentacles and is known for its venomous sting. It possesses gas glands that help it maintain buoyancy in the water.

- **Option 3: Pennatula (Sea Pen)**:
- Pennatula, or sea pen, is a type of soft coral that does not have gas glands. It has a different structure and method of buoyancy.

- **Option 4: Red Coral**:
- Red coral is primarily used in jewelry making and does not possess gas glands.

3. **Conclusion**:
- After analyzing all options, the organism that possesses gas glands is **Physalia (Man-of-war)**. Therefore, the correct answer is **Option 2**.

### Final Answer:
Gas glands occur in **Physalia (Man-of-war)**.

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