Parasympathetic fibres travelling in the vagus nerves provide secretomotor and motor supply to the gastrointestinal tract as far as a well-defined transition point. Distal to this point, parasympathetic supply comes from the sacral outflow. The transition occurs at the:

• A Splenic flexure ✓
• B Right two-thirds of the transverse colon
• C Duodenojejunal junction
• D Rectosigmoid junction

Explanation

Vagal parasympathetic fibres supply the entire foregut and midgut, ending at the junction of the proximal two-thirds and distal one-third of the transverse colon, close to the splenic flexure. This corresponds to the Cannon-Bohm point, the boundary between midgut and hindgut arterial supply. Beyond this point the pelvic splanchnic nerves (S2-S4) take over. The duodenojejunal junction marks no autonomic transition, and the rectosigmoid junction lies entirely within sacral territory.

Reference: Gray's Anatomy for Students, 4th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.