Choose the incorrect statement.

Options

A. Receptors associated with aortic arch can recognize changes in `H^+` concentration
B. A chemosensitive area is located adjacent to respiratory rhythm centre.
C. Chemosensitive area is highly sensitive to `CO_2`
D. The role of oxygen in the regulation of respiratory rhythm is quite significant .

Answer

To solve the question "Choose the incorrect statement," we will analyze each of the provided statements regarding the respiratory system and identify which one is incorrect.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The first statement claims that receptors associated with the aortic arch can recognize changes in H+ concentration.
- This statement is **correct** because the receptors in the aortic arch (chemoreceptors) do respond to changes in both H+ ions (which indicate acidity) and CO2 levels.

2. **Analyze the Second Statement:**
- The second statement mentions that a chemo-sensitive area is located adjacent to the respiratory rhythm center.
- This statement is also **correct**. The chemosensitive area (which is sensitive to CO2 levels) is indeed located near the respiratory rhythm center in the brain.

3. **Analyze the Third Statement:**
- The third statement discusses the role of oxygen in the regulation of respiratory rhythm, stating that it is quite significant.
- This statement is **incorrect**. While oxygen does play a role in respiration, its role in the regulation of the respiratory rhythm is considered to be **insignificant** compared to that of CO2. The primary drive for respiration is more closely related to CO2 levels rather than oxygen levels.

4. **Conclusion:**
- Based on the analysis, the **incorrect statement** is the third one, which states that the role of oxygen in the regulation of respiratory rhythm is quite significant. The correct assertion should be that it is insignificant.

### Final Answer:
The incorrect statement is: "The role of oxygen in the regulation of respiratory rhythm is quite significant."

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