<prompt> All are TRUE about Meckels diveiculum, EXCEPT:It occurs in 2 populationIt is a true diveiculumIt always contains gastric mucosaIt arises from antimesenteric border  <response>: Meckels diveiculum is the most prevalent congenital anomaly of the GI tract, affecting approximately 2 of the general population. A 3:2 male-to-female prevalence ratio has been repoed. Meckels diveicula are designated as true diveicula because their walls contain all of the layers found in normal small intestine. Approximately 60 of Meckels diveicula contain heterotopic mucosa, of which over 60 consist of gastric mucosa. It arises from the antimesenteric border of ileum. A useful mnemonic describing Meckels diveiculum is the rule of twos: 2 prevalence, 2:1 female predominance, location 2 ft proximal to the ileocecal valve in adults, and one half of those who are symptomatic are under 2 years of age. Ref: Tavakkolizadeh A., Whang E.E., Ashley S.W., Zinner M.J. 2010. Chapter 28. Small Intestine. In F.C. Brunicardi, D.K. Andersen, T.R. Billiar, D.L. Dunn, J.G. Hunter, J.B. Matthews, R.E. Pollock Eds, Schwazs Principles of Surgery, 9e. 