Why the heart does not require the nervous system to initiate contraction events
A)because it is parasympathetically innervated via cardiac nerve fibres
B)because it is parasympathetically innervated by vagus nerve fibres
C)because it is innervated by the sympathetic division of the autonomic nervous system only
D)because it is innervated by cortical nerve fibres

Question

Quizplus · Accepted Answer

The heart does not require the nervous system to initiate contraction events because it has its own intrinsic conduction system, capable of generating and propagating electrical impulses that trigger heart contractions. However, the parasympathetic innervation by the vagus nerve (choice B) can modulate heart rate by slowing it down, not initiate the contractions. The other options are incorrect because they either misrepresent the role of nervous system innervation or suggest incorrect sources of innervation.

Why the Heart Does Not Require the Nervous System to Initiate