Which function is served by the tracheal system in____ insects?

Options

A. Sensation
B. Respiration
C. Both 1 and 2
D. Digestion

Explanation

**Step-by-Step Solution:**

1. **Understanding the Tracheal System**: The tracheal system is a network of tubes that transport air directly to the tissues in insects. It is a specialized respiratory system found in members of the phylum Arthropoda, particularly in the class Insecta.

2. **Identifying Functions of the Tracheal System**: The primary function of the tracheal system in insects is to facilitate gas exchange. This means it is responsible for the intake of oxygen and the expulsion of carbon dioxide, which is essential for respiration.

3. **Evaluating the Options**:
- **Option 1: Sensation** - This is incorrect because sensation in insects is primarily managed by sensory organs such as antennae, not the tracheal system.
- **Option 2: Respiration** - This is correct as the tracheal system is directly involved in the respiratory process.
- **Option 3: Both 1 and 2** - This is incorrect since the tracheal system does not serve the function of sensation.
- **Option 4: Digestion** - This is also incorrect as digestion is handled by the digestive system, not the tracheal system.

4. **Conclusion**: Based on the evaluation of the options, the correct answer is that the tracheal system serves the function of respiration in insects.

**Final Answer**: The function served by the tracheal system in insects is respiration.

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