The carbon dioxide you breathe out is carried to the lungs in the blood. Carbon dioxide, when dissolved in water, is an acid. How does the body prevent your blood from becoming too acidic on the way to your lungs?

Question

Quizplus · Accepted Answer

Buffers in the blood accept hydrogen ions (H+) to prevent the blood from becoming too acidic. When carbon dioxide (CO2) is carried in the blood, it reacts with water (H2O) to form carbonic acid (H2CO3), which dissociates into hydrogen ions (H+) and bicarbonate ions (HCO3-). Buffers in the blood can accept these hydrogen ions to prevent the pH of the blood from becoming too low (acidic). When the blood reaches the lungs, the carbon dioxide is exhaled and the reaction runs in reverse, causing the pH to return to normal.

The Carbon Dioxide You Breathe Out Is Carried to the Lungs