Question

30. The contraction of cardiac muscles is caused by: A) Spontaneous stimuli B) Nervous stimuli C) Stretch stimuli D) Hormonal stimuli.​

Answer 1

Answer:

spontaneous stimuli

Explanation:

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Answer 2

Answer:

Introduction. Cardiac muscle contraction is an electrical event initiated at the sinoatrial node. Each cardiac muscle cell fires an action potential as a result of excitation propagated from the sinoatrial node, which produces muscle cell contraction.