Heart valves open and close because of
A) pressure differences.
B) heart contractions.
C) signals from the SA node.
D) contractions of the papillary muscles.
E) the moderator band.

Question

Quizplus · Accepted Answer

Heart valves open and close due to pressure differences. As the heart contracts, pressure in the chambers change, causing the valves to open and close in response to these pressure changes.

Heart Valves Open and Close Because of