Meckel’s diverticulum is a remnant of -

The Vitellointestinal duct or the omphalomesenteric duct is the connection between the yolk sac and the developing gut. Normally, it gets obliterated and disappears. But sometimes it may persist in various forms giving rise to congenital anomalies:- Umbilical faecal fistula - due to the persistence of the entire vitellointestinal duct. Umbilical sinus - when the duct is obliterated at the intestinal end but communicates with the umbilicus at the distal end. Meckel’s diverticulum - when the duct is obliterated at the umbilicus but persists at it intestinal end. Umbilical cyst or vitelline cyst - when both ends are occluded but the track in between persists. Fibrous band - the entire track may be obliterated, but a fibrous band may persist between the ileum and the umbilicus. The fibrous band may lead to intestinal obstruction.