This is A.P. of cardiac muscle. Phase 3 is due to: Phase 1 Phase 2 Phase 3 Phase 0 Phase 4 Phase 4 O movement of fewer sodium ions across the cell membrane. increased membrane permeability to...

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Extracted text: This is A.P. of cardiac muscle. Phase 3 is due to: Phase 1 Phase 2 Phase 3 Phase 0 Phase 4 Phase 4 O movement of fewer sodium ions across the cell membrane. increased membrane permeability to potassium ion. O calcium channels remaining open. O increased membrane permeability to sodium ions. decrease in the amount of calcium diffusing across the membrane. acer