Question

Match the channel type with the appropriate description.

Opening of these channels is responsible for the depolarization phase of the cardiac contractile cell action potential.


A) voltage-gated sodium channels
B) potassium channels
C) funny channels
D) T-type calcium channels
E) L-type calcium channels

Answer 1

The voltage-gated sodium channels are responsible for the depolarization phase of the cardiac contractile cell action potential.

Step-by-step explanation:

The channel type responsible for the depolarization phase of the cardiac contractile cell action potential is the voltage-gated sodium channels (A). When the membrane potential reaches the threshold of -55 mV, these channels open and allow sodium ions to enter the cell, causing depolarization. This initiates the action potential.