Ventilation movements in Cockroach are performed

Options

A. At rest
B. During activity
C. All the times
D. When threatened

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about when ventilation movements in cockroaches occur, specifically whether they happen at rest, during activity, all the time, or when threatened.

2. **Identifying the Body Structure**: Cockroaches are insects, which belong to the phylum Arthropoda. Their bodies are divided into three main parts: the head, thorax, and abdomen.

3. **Understanding Ventilation Movements**: Ventilation movements refer to the process of gas exchange, specifically the exchange of respiratory gases (oxygen and carbon dioxide) that occurs in the cockroach.

4. **Identifying the Mechanism of Gas Exchange**: In cockroaches, gas exchange occurs through small openings on their body surface called spiracles. These spiracles lead to an extensive network of tracheal vessels that facilitate respiration.

5. **Determining When Ventilation Occurs**: The key point is that the exchange of gases primarily occurs during activity. This means that when the cockroach is active, it requires more oxygen, leading to increased ventilation movements.

6. **Evaluating the Options**:
- At rest: Incorrect, as ventilation does not occur significantly at rest.
- During activity: Correct, as ventilation movements are most prominent during activity.
- All times: Incorrect, as ventilation is not constant.
- When threatened: Incorrect, as it is not specifically tied to threats.

7. **Conclusion**: The correct answer is that ventilation movements in cockroaches occur during activity.

### Final Answer:
**Ventilation movements in cockroaches are performed during activity.**

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