Which pattern of small bowel motility is responsible for clearing undigested residue and bacteria from the small intestine during fasting?
- A Migrating motor complex (MMC) ✓
- B Peristalsis
- C Segmentation
- D Tonic contraction
Correct answer: A. Migrating motor complex (MMC)
Explanation
The migrating motor complex (MMC) is a cyclical pattern of electromechanical activity in the small intestine during fasting, recurring every 90-120 minutes. Phase III of the MMC produces a powerful peristaltic wave that sweeps undigested residue, desquamated cells, and bacteria from the small bowel into the colon, serving a 'housekeeper' function. Segmentation mixes chyme during digestion.
Reference: Ganong's Review of Medical Physiology, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.