While doing sigmoidoscopy, if the rectum is inflated with gas, increased peristalsis is seen in: (A) Whole colon, (B) Proximal colon, (C) Distal colon, (D) Whole intestine
Answer is C. Defecation reflex - When the rectum is distended, a reflex propulsive movement from descending colon to rectum occurs. Along with that, the internal anal sphincter relaxes. The same happens when the rectum is distended by gas.