For the Majority of the GI Tract, Which Layer(s)of the Wall

Question

For the majority of the GI tract, which layer(s)of the wall contains smooth muscle?
A) muscular layer and serosa
B) mucosa and adventitia/serosa
C) adventitia/serosa
D) mucosa and muscular layer
E) submucosa and muscular layer

Accepted Answer

The muscular layer of the GI tract contains smooth muscle and is responsible for the movement of food and waste through the digestive system. The mucosa layer lines the innermost part of the GI tract and is responsible for absorption and secretion. Therefore, the correct answer is D as it includes both the muscular layer and mucosa layer.