Which of the following best describes the pathway an oxygen molecule would take through the human circulatory system?
A)systemic tissues → alveoli → pulmonary vein → pulmonary capillaries → systemic capillaries → left ventricle → left atrium → aorta → systemic arteries
B)alveoli → pulmonary capillaries → pulmonary vein → left atrium → left ventricle → aorta → systemic arteries → systemic capillaries → systemic tissues
C)alveoli → pulmonary capillaries → pulmonary artery → right atrium → right ventricle → pulmonary vein → systemic arteries → systemic capillaries → systemic tissues
D)alveoli → pulmonary vein → pulmonary capillaries → systemic capillaries → left atrium → left ventricle → aorta → systemic arteries → systemic tissues

Question

Quizplus · Accepted Answer

Oxygen molecules enter the body through the alveoli in the lungs, where they diffuse into the pulmonary capillaries. From there, they are carried by the pulmonary vein to the left atrium of the heart and then to the left ventricle, which pumps oxygenated blood into the aorta. The aorta then carries the blood to the systemic arteries, which deliver oxygen to the tissues via the systemic capillaries.

Which of the Following Best Describes the Pathway an Oxygen