Blood in the Pulmonary Artery Has a Lower PH Than

Question

Blood in the pulmonary artery has a lower pH than the blood in the aorta.

Accepted Answer

Blood in the pulmonary artery is coming from the right ventricle of the heart and has not yet been oxygenated. As a result, it contains higher levels of carbon dioxide, which forms carbonic acid, leading to a lower pH. In contrast, blood in the aorta has been oxygenated in the lungs and therefore has a higher pH.