What effect would an increase in venous return have on the stroke volume?
A)An increase in venous return would fill the ventricles with more blood,decreasing sarcomere length,which would decrease the stroke volume.
B)An increase in venous return would fill the ventricles with more blood,increasing sarcomere length,which would increase the stroke volume.
C)An increase in venous return would fill the ventricles with less blood,decreasing sarcomere length,which would increase the stroke volume.
D)An increase in venous return would fill the ventricles with less blood,decreasing sarcomere length,which would decrease the stroke volume.
E)An increase in venous return would fill the ventricles with less blood,increasing sarcomere length,which would decrease the stroke volume.

Question

Quizplus · Accepted Answer

An increase in venous return would fill the ventricles with more blood, which would increase the preload of the heart. This would result in an increase in sarcomere length and stretch of the ventricular muscle fibers, known as the Frank-Starling mechanism. The increase in sarcomere length would lead to an increase in stroke volume, as the heart muscle fibers would have a greater contractile force due to increased stretch. Therefore, an increase in venous return would increase stroke volume.

What Effect Would an Increase in Venous Return Have on the Stroke