If the `CO_2` concentration in the blood increases, the rate of breathing will

Options

A. decrease
B. stop
C. increase
D. have no effect

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of CO2 in Blood:**
- Carbon dioxide (CO2) is a waste product produced by cells during respiration. Its concentration in the blood is an important factor that regulates breathing.

2. **Increase in CO2 Concentration:**
- When the concentration of CO2 in the blood increases, it indicates that the body is producing more CO2 than it is expelling.

3. **Stimulation of the Respiratory Center:**
- The increase in CO2 levels is detected by chemoreceptors in the body, particularly in the brain. The respiratory center, located in the medulla oblongata and pons, gets stimulated in response to high CO2 levels.

4. **Response of the Respiratory System:**
- The stimulation of the respiratory center leads to an increase in the rate and depth of breathing. This is the body’s way of trying to expel the excess CO2 and take in more oxygen.

5. **Conclusion:**
- Therefore, if the CO2 concentration in the blood increases, the rate of breathing will increase.

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