Some neurons in the vagus nerve have synaptic connections to sinoatrial (pacemaker) cells in the heart. These neurons secrete acetylcholine, which ultimately results in a decreased heart rate. This is an example of
A) endocrine control
B) exocrine control
C) hormonal control
D) neural control
E) paracrine control

Question

Quizplus · Accepted Answer

This is an example of neural control, as the neurons in the vagus nerve are communicating with and affecting the activity of pacemaker cells in the heart. The secretion of acetylcholine serves as a neurotransmitter in this communication between neurons and the heart. Endocrine control involves the release of hormones into the bloodstream to affect distant target cells, exocrine control involves the secretion of substances onto epithelial surfaces or into ducts, hormonal control is another term for endocrine control, and paracrine control involves the release of substances that affect nearby cells.

Some Neurons in the Vagus Nerve Have Synaptic Connections to Sinoatrial