Question

If the $C{O}_2$ concentration in the blood increases, the breathing shall.

• A. Increase
• B. Decrease
• C. Stop
• D. No affect

Answer 1

The correct option is A Increase

• The increase in carbon dioxide concentration in blood increases the rate of breathing.
  
• The increase in carbon dioxide brings a remarkable change in the pH of the blood. This change is sensed by the chemoreceptors of the medulla oblongata of the hindbrain which has a regulatory centre for respiration.
  
• The respiratory centre increases the rate of respiration to exhale the extra carbon dioxide and inhale more oxygen.

So, the correct answer is option A.