QUESTION 5 Layer of the GI tract responsible for segmentation. serosa muscularis externa submucosa lamina propria muscularis mucosae

The layer of the GI tract responsible for segmentation is the muscularis externa. This layer contains two types of smooth muscle: an inner circular layer and an outer longitudinal layer. The rhythmic contractions of these muscles mix and propel food through the digestive tract, playing a key role in digestion and absorption. Segmentation is particularly prominent in the small intestine, where food is mixed with digestive juices. This mixing enhances nutrient absorption by allowing for a longer contact time between the food and the intestinal walls, showcasing how the muscularis externa not only moves food along but also aids in breaking it down more efficiently.