Which one of the following structures is well-developed in hydrophytes?

Options

A. Aerenchyma
B. Collenchyma
C. Stomata
D. Root system

Answer

To solve the question "Which one of the following structures is well-developed in hydrophytes?" we will analyze the options provided: Aranchyma, Collenchyma, Stomata, and Root System.

### Step-by-Step Solution:

1. **Understanding Hydrophytes**:
- Hydrophytes are plants that grow in water or in very moist environments. They have specialized adaptations to thrive in such conditions.

2. **Analyzing Aranchyma**:
- Aranchyma is a type of tissue that contains large air spaces (aerenchyma) which facilitate buoyancy and gas exchange. This structure is well-developed in hydrophytes as it helps in the exchange of gases between the submerged parts and the atmosphere.

3. **Analyzing Collenchyma**:
- Collenchyma is a supportive tissue that provides mechanical strength to young and growing parts of the plant. However, it is not particularly well-developed in hydrophytes because these plants do not require as much structural support due to their buoyant environment.

4. **Analyzing Stomata**:
- Stomata are small openings on the surfaces of leaves that allow for gas exchange (CO2 intake and water vapor release). In hydrophytes, stomata are often reduced or absent because these plants are submerged in water, which reduces the need for transpiration.

5. **Analyzing Root System**:
- The root system in hydrophytes is often less developed compared to terrestrial plants. Many hydrophytes have shallow roots or floating roots, as they do not need to anchor deeply in soil.

6. **Conclusion**:
- Based on the analysis, the structure that is well-developed in hydrophytes is **Aranchyma**. This specialized tissue is crucial for their survival in aquatic environments.

### Final Answer:
**Aranchyma** is the structure that is well-developed in hydrophytes.

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