Question

Does the sympathetic or parasympathetic nervous system cause contraction of the digestive tract smooth muscle?

1) Sympathetic nervous system
2) Parasympathetic nervous system
3) Both sympathetic and parasympathetic nervous systems
4) Neither sympathetic nor parasympathetic nervous system

Answer 1

The parasympathetic nervous system is responsible for the contraction of digestive tract smooth muscle, facilitating peristalsis and movement of food through the GI tract. The correct option is 2.

Step-by-step explanation:

The contraction of smooth muscle in the digestive tract is primarily controlled by the parasympathetic nervous system, which is part of the autonomic nervous system responsible for the 'rest-and-digest' response. When stimulated, the parasympathetic system increases gastrointestinal (GI) secretion and motility, promoting the movement of food along the digestive tract through a process known as peristalsis.

In contrast, the sympathetic nervous system is associated with the 'fight-or-flight' response, and its activation typically restricts the activity of enteric neurons, thereby decreasing GI secretion and motility which can lead to the contraction of sphincters to limit digestive propulsion. Hence, 2 is the correct option.