When `CO_(2)` concentration in blood increases breathing becomes

Options

A. Increase
B. Decrease rapidly
C. Stop
D. Remain unchanged

Answer

**Step-by-Step Solution:**

1. **Understanding CO2 Levels in Blood:**
- When the concentration of carbon dioxide (CO2) in the blood increases, it indicates that the body is producing more CO2 than it is eliminating. This can happen during exercise or due to respiratory issues.

2. **Stimulating the Respiratory Centers:**
- The increase in CO2 concentration is detected by chemoreceptors in the body, particularly in the brain and blood vessels. These chemoreceptors send signals to the respiratory centers in the brain to respond to the elevated CO2 levels.

3. **Response of the Respiratory System:**
- The respiratory centers respond by increasing the rate and depth of breathing. This response is known as hyperventilation. Hyperventilation is characterized by an increase in pulmonary ventilation, which means that more air is being moved in and out of the lungs.

4. **Effects of Hyperventilation:**
- During hyperventilation, both the rate (how fast you breathe) and the force (how deeply you breathe) of breathing increase. This means that the person will breathe faster and take deeper breaths.

5. **Conclusion:**
- Therefore, when CO2 concentration in the blood increases, breathing becomes faster and deeper, which can be summarized as "increased."

**Final Answer:**
When CO2 concentration in blood increases, breathing becomes increased (faster and deeper).

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