SAT Subject Biology Practice Question 401: Answer and Explanation
Which of the following represents the correct sequence of heart structures that blood would pass through when traveling from the right atrium to the lungs and then to the left ventricle?
A. 3, 2, 4, 5, 7
B. 6, 2, 1, 4, 5
C. 3, 2, 1, 5, 7
D. 6, 2, 3, 4, 5
E. 6, 2, 4, 5, 7
Correct Answer: E
E You need to know the pathway that blood takes through the heart and some basic heart anatomy (names of chambers and vessels). Beginning at the right atrium, the next chamber blood enters is the right ventricle, which on this diagram is labeled "6." Because choices A and C do not start with "6" they can be eliminated. All of the remaining choices then contain structure 2 (the pulmonary artery), which is the next structure in sequence. From the pulmonary artery, blood flows to the lungs, then returns to the heart through the pulmonary veins, labeled "4" on the diagram. This eliminates choices B and D. Note that you don't have to worry about the rest of the sequence, because you have already eliminated all other answer choices (although "5," the left atrium, and "7," the left ventricle, are the correct structures in sequence).