"Artery" and "vein" are defined by whether they leave or enter the heart. If they were defined by whether they carried oxygenated or deoxygenated blood, we would have to change the name(s) of
A) the hepatic portal vein to a hepatic portal artery.
B) the hepatic and renal systems; they would have to be switched.
C) the pulmonary artery and vein; they would have to be switched.
D) the coronary artery and vein; they would have to be switched.
E) none, since the aorta and vena cava do not have "artery" and "vein" in their name.

Question

Quizplus · Accepted Answer

The pulmonary artery carries deoxygenated blood from the heart to the lungs, while the pulmonary vein carries oxygenated blood from the lungs to the heart. However, they are still named as artery and vein respectively, which would contradict the definition if they were based on oxygenation status. Therefore, their names would have to be switched if they were defined by whether they carried oxygenated or deoxygenated blood.

"Artery" and "Vein" Are Defined by Whether They Leave or Enter