During contraction of heart muscle cells ________.
A) the action potential is initiated by voltage-gated slow calcium channels
B) some calcium enters the cell from the extracellular space and triggers the release of larger amounts of calcium from intracellular stores
C) the action potential is prevented from spreading from cell to cell by gap junctions
D) calcium is prevented from entering cardiac fibers that have been stimulated

Question

Quizplus · Accepted Answer

During contraction of heart muscle cells, some calcium enters the cell from the extracellular space and triggers the release of larger amounts of calcium from intracellular stores. This process is called calcium-induced calcium release and is responsible for the contraction of the myocardium.

During Contraction of Heart Muscle Cells ________