Motility of the Small Intestine – GIT Physiology Summary

Course Title: GIT – Gastrointestinal Tract
Topic: Motility of the Small Intestine
School: ANCHOR UNIVERSITY
Semester: 2nd Semester, 2025


INTRODUCTION
The small intestine is crucial for digesting food and absorbing nutrients. Its motility mixes
food with enzymes and moves it along the tract. These movements are controlled by
nerves and hormones to ensure efficient digestion and absorption.
Types of Motility in the Small Intestine:
• Segmentation: Rhythmic contractions of circular muscles that mix chyme and
bring it into contact with the mucosal surface for absorption.
• Peristalsis: Coordinated, wave-like contractions that propel chyme forward
through the intestine.
• Migrating Motor Complex (MMC): A cyclic motility pattern during fasting that
cleans residual food and secretions from the intestine.




Figure 1: Types of Small Intestine Motility
Control of Small Intestine Motility:
• Enteric Nervous System (ENS): Myenteric plexus controls smooth muscle
contractions locally.
• Autonomic Nervous System:
o Parasympathetic stimulation enhances motility.