Final answer:
Increased production of carbon dioxide in the body leads to a decrease in blood pH due to the formation of carbonic acid and a rise in hydrogen ions, creating an acidic environment.
Step-by-step explanation:
When the body produces more carbon dioxide, it forms carbonic acid (H2CO3) which disassociates into bicarbonate (HCO3-) and hydrogen ions (H+), causing the blood pH to drop. This represents a more acidic environment in the blood. During periods of high activity, cells increase cellular respiration leading to a rise in carbon dioxide, generating a surplus of hydrogen ions, which further decreases pH. Conversely, when resting, oxygen levels are higher and carbon dioxide levels are lower, allowing more hydrogen to be bound, resulting in a higher pH level. Through the respiration process, the body can regulate pH by adjusting the rate of breathing which changes the amount of carbon dioxide that is exhaled.