What physiological response does the body have to elevated carbon dioxide levels?

What physiological response does the body have to elevated carbon dioxide levels?

• A. Decrease respiratory rate
• B. Increase metabolic rate
• C. Stimulate increased breathing rate
• D. Increase heart rate

Answer: (C)

When carbon dioxide levels in the blood rise, a physiological response is initiated to restore balance to the body’s acid-base status through respiratory mechanisms. The elevation of carbon dioxide (hypercapnia) leads to an increase in the concentration of carbonic acid, causing a decrease in blood pH (making it more acidic). In response to this hypercapnia, the central chemoreceptors located in the medulla oblongata of the brain detect the increased carbon dioxide and the resulting lower pH. This triggers the respiratory centers to stimulate an increase in the breathing rate and depth (hyperventilation). The body aims to expel excess carbon dioxide by increasing ventilation, thereby helping to restore normal levels of carbon dioxide and regulate blood pH back to the normal range. This response is crucial as maintaining proper carbon dioxide levels is essential for homeostasis, influencing not only respiration but also other physiological processes. Other potential choices such as decreasing respiratory rate or increasing metabolic rate are not effective responses to high carbon dioxide levels, as they would exacerbate the situation rather than correct it. Increasing heart rate can occur in response to various stimuli, but it is not a direct response to elevated carbon dioxide levels in the same way that increased breathing rate is.

When carbon dioxide levels in the blood rise, a physiological response is initiated to restore balance to the body’s acid-base status through respiratory mechanisms. The elevation of carbon dioxide (hypercapnia) leads to an increase in the concentration of carbonic acid, causing a decrease in blood pH (making it more acidic).

In response to this hypercapnia, the central chemoreceptors located in the medulla oblongata of the brain detect the increased carbon dioxide and the resulting lower pH. This triggers the respiratory centers to stimulate an increase in the breathing rate and depth (hyperventilation). The body aims to expel excess carbon dioxide by increasing ventilation, thereby helping to restore normal levels of carbon dioxide and regulate blood pH back to the normal range.

This response is crucial as maintaining proper carbon dioxide levels is essential for homeostasis, influencing not only respiration but also other physiological processes. Other potential choices such as decreasing respiratory rate or increasing metabolic rate are not effective responses to high carbon dioxide levels, as they would exacerbate the situation rather than correct it. Increasing heart rate can occur in response to various stimuli, but it is not a direct response to elevated carbon dioxide levels in the same way that increased breathing rate is.