The step labeled 5 in the diagram of blood flow through the heart shows oxygenated blood returning from the lungs and entering the left atrium through the

Question

Quizplus · Accepted Answer

Oxygenated blood returns from the lungs through the pulmonary veins and enters the left atrium, as depicted in step 5 of the blood flow diagram. Therefore, the best choice is E, which represents the pulmonary veins. Choices A and B represent the major vessels that carry blood to and from the heart, but they do not directly relate to oxygenated blood returning from the lungs. Choice C represents veins in the neck that drain blood from the head and neck, but again, they are not directly related to oxygenated blood returning from the lungs. Choice D represents the vessels that carry deoxygenated blood from the heart to the lungs, which is the opposite of the direction of flow in step 5.

The Step Labeled 5 in the Diagram of Blood Flow