Question 139
(Multiple Choice)
Figure 20-2 Cardiac Cycle
Use Figure 20-2 to answer the following questions:
-What occurs at the area labeled "B" on the graph?
A) Ventricular ejection occurs.
B) AV valve closes.
C) Semilunar valve opens.
D) Semilunar valve closes.
E) AV valve opens.
Answer