Final answer:
The respiratory system can increase blood pH by a hyperventilation-induced decrease in the levels of carbon dioxide, which reduces carbonic acid and thus raises the pH, making the blood more alkaline.answer is option B.
Step-by-step explanation:
The activity of the respiratory system can increase pH by a hyperventilation-induced decrease in PCO2. When we hyperventilate, we increase ventilation rate, which leads to lower levels of carbon dioxide in the blood (abnormally low blood carbon dioxide levels). The decrease in carbon dioxide (CO2) levels reduces the amount of carbonic acid in the blood since CO2 readily reacts with water to form it. As a result, there's a decrease in hydrogen ion concentration, which in turn increases the systemic pH; thus, making the blood more alkaline.
During states of metabolic acidosis, the body compensates by increasing the respiratory rate to drive off excess CO2, aiding in restoring pH balance. The relationship between CO2 and pH is part of the body's buffering system, involving the bicarbonate to carbonic acid ratio. If the blood becomes too acidic (low pH), an increase in breathing helps remove CO2, while if the blood is too alkaline (high pH), a lower breath rate can help increase CO2 concentration and adjust pH towards normal levels.