Question

Short / long answer type questions.
The rate of respiration usually depends on $C{O}_2$ tension of the arterial blood. Give one specific reason.

Answer 1

• The level of C02 in the blood is the most important influence on the regulation of ventilation. The blood level of C02 acts directly on the respiratory centers in the medulla and is a major influence on cerebrospinal fluid pH.
• An increase in C02 level leads to an increase in ventilation by stimulating phrenic and intercostal nerves that activate the respiratory muscles.
  
• It is significant because small changes in C02 concentration can be detected unlike that of oxygen.