Action potentials generated by the autorhythmic cells spread to the contractile cells through what structures in the membrane?

Answer;

Gap junctions

Explanation;Gap junctions allow the exchange of ions, second messengers, and small metabolites between adjacent cells and are formed by two unrelated protein families, the pannexins and connexins. Action potentials generated by the autorhythmic cells spread waves of depolarization to contractile cells through gap junctions. If the depolarization causes the contractile cells to reach threshold, they will in turn generate an action potential.

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