The long plateau phase of the cardiac muscle action potential is due to

The Cardiac Muscle

Explanation:

The long plateau phase of the cardiac muscle action potential is due to Calcium channels remaining open.Depolarization is trailed by the plateau phase wherein film potential decreases generally gradually. This is expected in enormous part to the opening of the moderate Ca2+ channels, permitting Ca2+ to enter the cell while few K+ channels are open, permitting K+ to leave the cell.  During stage 1, there is halfway repolarization, in view of an abatement in sodium porousness. Stage 2 is the plateau phase  of the cardiovascular activity potential. Film penetrability to calcium increments during this stage, keeping up depolarization and dragging out the activity potential.

Ithink it's c (70)

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