The depolarization phase of the cardiac muscle action potential occurs when
a. voltage-gated Ca2+ ion channels open.
b. voltage-gated K+ ion channels open.
c. voltage-gated Na+ ion channels open.
d. both b and c
Answer: C
The depolarization phase of the cardiac muscle action potential occurs when
a. voltage-gated Ca2+ ion channels open.
b. voltage-gated K+ ion channels open.
c. voltage-gated Na+ ion channels open.
d. both b and c