Final answer:
Ventilation increases in response to high levels of carbon dioxide in the blood, which causes a decrease in blood pH. Peripheral chemoreceptors sense the acidic pH and stimulate the body to hyperventilate, expelling CO2 and increasing the blood pH. Hyperventilation is distinct from hyperpnea, which is driven by oxygen demand and does not significantly change blood CO2 levels.
Step-by-step explanation:
Factors Influencing Ventilation
To understand what increases ventilation, it's essential to know the relation between ventilation rate, carbon dioxide (CO2) levels, and blood pH. When CO2 levels in the blood rise, it leads to an increase in hydrogen ions (H+), which decreases the pH, making the blood more acidic. The body responds by increasing ventilation to expel the excess CO2, restoring the pH to a more alkaline state. This process is called hyperventilation, which is an increased ventilation rate that leads to abnormally low blood CO2 levels and higher blood pH.
The relationship between respiratory rate and volume of air per breath can vary:
- If ventilation is low, the respiratory rate can either decrease with an increased volume per breath or increase with a decreased volume per breath.
- High ventilation typically involves an increased respiratory rate, with either an increased or decreased volume per breath, depending on the circumstances.
Peripheral chemoreceptors in the aortic arch and carotid arteries play a crucial role. They monitor arterial levels of hydrogen ions and, when they detect more acidic blood pH, stimulate an increase in ventilation to quicker remove CO2 and bring the pH back to a normal range.
Hyperpnea also increases the rate and depth of ventilation due to a rise in oxygen demand but doesn't significantly alter blood oxygen or CO2 levels. This differs from hyperventilation, where the key outcome is the reduction of blood CO2 levels and increased alkalinity of the blood.