The greatest difference in the concentration of respiratory gases is found in which of the following pairs of mammalian blood vessels? the greatest difference in the concentration of respiratory gases is found in which of the following pairs of mammalian blood vessels? the pulmonary artery and the inferior vena cava the pulmonary vein and the aorta the veins from the right and left legs the pulmonary vein and the superior vena cava

The correct answer would be the pulmonary vein and the superior vena cava.

Pulmonary vein is a blood vessel of pulmonary circulation which carries oxygenated blood from lungs to the left atrium of the heart. Hence, it is rich in oxygen and carries carbon dioxide in the least amount.

In contrast, vena cava is a part of systemic circulation and carries deoxygenated blood from the body to the right atrium of the heart. They are two venae cavae in human beings namely; inferior vena cava (carries blood from lower body) and superior vena cava (carries blood from head, arms and upper body). Hence, it contains maximum carbon dioxide and least oxygen.

the correct answer would be 6 feet.

if you listed your answers right then i believe your answer is b.