(D) Lesser omentum (SAC)[?]Portion of the dorsal mesentery that attaches to the greater curvature of the stomach to the posterior abdominal wall is known as the dorsal mesogastrium.Part of the dorsal mesentery that suspends the colon is termed the mesocolon.Dorsal mesogastrium develops into the greater omentum.[?]Fate of Dorsal Mesogastrium:Most of it forms the greater omentum.Dorsal mesogastrium between stomach & spleen becomes the gastrosplenic ligament & the part between the spleen & kidney becomes lienorenal (splenorenal) ligamentSpleen remains intra-peritoneal.[?]Derivatives of the Mesenteries of the Fore-gutDorsal Mesoesophagus: Crura of the DiaphragmVentral Mesoesophagus: Disappears completelyDorsal Mesogastrium: Lienorenal ligament, Gastrosplenic lig.Ventral Mesogastrium: Lesser omentum, Visceral peritoneum of the liver, Falciform ligament of the liverDorsal mesentery of the duodenum: persists in the proximal part (one inch) as hepatoduodenal ligament.Ventral mesentery of the Duodenum: Disappears almost completelyDerivatives of Dorsal Mesogastrium[?]Dorsal Mesogastrium:Extends from the greater curvature to the posterior abdominal wall.Derivatives:SpleenGastrosplenic omentumLienorenal ligamentGreater omentumDerivatives of Ventral Mesogastrium[?]Ventral Mesogastrium:Extends from the lesser curvature to septum trans- versum & anterior abdominal wall.Derivatives:Falciform ligamentRight & left triangular ligaments.Superior & Inferior layers of coronary ligamentsLesser omentumDEVELOPMENT OF ALIMENTARY SYSTEM AT GLANCEEpithelium of G.I.T. (Except part of oral cavity and lower part of anal canal) is endodermal in origin.Glands associated with G.I.T. (Except Parotid salivary gland) are endodermal in origin.Muscles, connective tissue, & peritoneum are splanchnopleuric mesodermal in origin.Gut tube is divided into Fore-gut, Mid-gut & Hind gut. Cranial most part of gut tube forms pharynx.Remaining part of fore-gut gives rise to oesophagus, stomach, duodenum up to the point of entry of bile duct, parenchyma of liver & pancreas.Mid-gut loop cranial to the artery is Pre-arterial segment and caudal to the artery is Post-arterial segment.Derivatives of mid gut loop are duodenum below the entry of bile duct, jejunum, ileum, caecum, appendix, ascending colon, right & middle thirds of transverse colon.Abnormalities of rotation of gut may be of irregular sequence in the reduction of umbilical hernia or derangement after return of gut to abdominal cavity.Hind gut caudal to allantois is cloaca.Cloaca is divided into ventral primitive urogenital/sinus and dorsal primitive rectum by a urorectal septum.Cloacal membrane which covers the cloaca is divided by the attachment of urorectal septum into ventral urogenital membrane (in relation to primitive urogenital sinus) and an anal membrane (in relation to primitive rectum).Hind gut & Cloacal derivatives are left third of transverse colon, descending and pelvic colons, rectum and upper part of anal canal, and a part of genitourinary system.Proctodeum develops into terminal part of anal canal.Rupture of anal membrane establishes continuity of anal canal.Superior mesenteric artery forms the axes of mid-gut loop dividing it into pre & post arterial segmentsParotid gland is ectodermal in origin and Submandibular & Sublingual glands are endodermal in origin