A 24-year-old healthy college student enrolls in a study to investigate the factors that influence blood oxygen content. The experiment is carried out at sea level, on room air with no additional oxygen. A method is developed to accurately measure the partial pressure of oxygen in the blood as it flows through the circulation. Blood is drawn from the vena cavae, alveolar capillaries, and aorta. All data are plotted, and the resulting curve is depicted in the graph below. Which of the following factors most likely explains the change in partial pressure indicated by the arrow?

Question

A 24-year-old healthy college student enrolls in a study to investigate the factors that influence blood oxygen content. The experiment is carried out at sea level, on room air with no additional oxygen. A method is developed to accurately measure the partial pressure of oxygen in the blood as it flows through the circulation. Blood is drawn from the vena cavae, alveolar capillaries, and aorta. All data are plotted, and the resulting curve is depicted in the graph below.  Which of the following factors most likely explains the change in partial pressure indicated by the arrow?

Quizplus · Accepted Answer

Eductional Objective: Because of the mixing of oxygenated blood from the pulmonary veins with deoxygenated blood from the bronchial circulation and thebesian veins, the pO₂ in the left atrium and ventricle is lower than that in the pulmonary capillaries.

A 24-Year-Old Healthy College Student Enrolls in a Study to Investigate