Difficulty: Medium
Average Score: 81%
Simulated
What does preload refer to?
Correct answer
B
Rationale
Preload refers to the volume of blood that enters the right side of the heart. This volume stretches the fibers in the heart before contraction. Preload is an essential factor in determining the force of ventricular contraction. Choices A, C, and D are incorrect. Choice A is incorrect because preload is specifically related to the volume of blood entering the right side of the heart. Choices C and D are incorrect as they refer to afterload, which is the pressure that the heart must overcome to pump blood out of the ventricles into the systemic or pulmonary circulation.