Which layer of the digestive tract controls digestive propulsion?

A. serosa

B. mucosa

C. submucosa

D. muscularis externa

D. muscularis externa

Explanation:

The gastrointestinal tract or digestive tract consist of four main layers:

• Mucosa - consists of the epithelium together with glandular tissue and the lamina propria (connective tissue)

• Submuscosa - consists of fibrous connective tissue with larger blood vessels, lymphatics, nerves ...

• Muscularis externa-smooth muscle layer that consists of three layers, responsible for movement (propulsion) and physical break down of the food

• Serosa-consists of connective tissue continuous with the peritoneum.