Question

In the ventricular action potential, name what phase and where each electrolyte conductance is greatest.

Phase 0-3
a) Phase 0: Sodium; Phase 1: Calcium; Phase 2: Potassium; Phase 3: Sodium
b) Phase 0: Potassium; Phase 1: Sodium; Phase 2: Calcium; Phase 3: Potassium
c) Phase 0: Sodium; Phase 1: Potassium; Phase 2: Calcium; Phase 3: Sodium
d) Phase 0: Calcium; Phase 1: Sodium; Phase 2: Potassium; Phase 3: Calcium

Answer 1

The conductance of electrolytes in the ventricular action potential varies in each phase, with sodium being highest in Phase 0, calcium in Phase 1, potassium in Phase 2, and sodium again in Phase 3.

Step-by-step explanation:

The correct answer is (a) Phase 0: Sodium; Phase 1: Calcium; Phase 2: Potassium; Phase 3: Sodium. In the ventricular action potential, the conductance of each electrolyte is different in each phase. Phase 0, which represents rapid depolarization, has the greatest sodium conductance. Phase 1, which represents early repolarization, has the greatest calcium conductance. Phase 2, which represents the plateau phase, has the greatest potassium conductance. Phase 3, which represents late repolarization, has the greatest sodium conductance.