cardiac muscle

the specialized muscle tissue of the heart. It consists of striated fibers that branch and interlock and are in electrical continuity with each other. This arrangement permits action potentials to spread rapidly from cell to cell, allowing large groups of cells to contract in unison. Compare skeletal muscle; smooth muscle.

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Psychology term of the day

March 15th 2025

helplessness

n. a state of incapacity, vulnerability, or powerlessness associated with the perception that one cannot do much to improve a negative situation that has arisen. Theorists have suggested that helplessness underlies various forms of anxiety, dependence, withdrawal, and demoralization. See also coping potential; learned helplessness. —helpless adj.