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- 1. P. 2 The GIT is derived from stomodeum, gut tube, proctodeum The surface ectoderm evaginate into the tissue in both stomodenum and proctodum. B/n the stomodeum and cephalic end of forget and b/n proctodum and causal end of hind gut, there is no formation of mesoderm. The surface ectoderm has direct contact with the endoderm. If it forms mesoderm it cause congenial anomali The communication of oral cavity and pharynx will be open b/c orophargnagal membrane disappears Caudal end of hind gut and surfact ectoderm of proctodeum will fuse and form anal members, then it rupture and form a continuity P.3 Two part of pharynagnal arch... mandibular and maxilary P.4 Failure of reciprocal induction there will be no formation of teeth. P.6 Deciduous teeth erupt from 6 month to 2 years Permanent teeth erupt from 6 to 18/25 years P. 10 Lamina stage shows the primordial of teeth P. 21 Occipital myotomes are 4 in number but one will degenerate and the others gives rise to muscle of the tongue. P. 23 Foramen cecum is the starting point for thyroid gland. Then it form temporary duct which is called thyroglossal duct which connects the tongue to the thyroid gland... and later on the duct will disappear or it cause congenial anomali like fistula (if it is opened) and cyst (if it swells). P. 32 There are 3 prominence:- fronto-nasal prominence, maxilary prominence and mandibular prominence.
- 2. P. 37 Anterior cleft due to primary palate development deficiency P. 38 Posterior cleft can go as far as uvula P. 42 Dorsal part of umbilical vesicle forms gut tube. Head fold result in incorporation of dorsal part of umbilical vessicle to the abdominal cavity as gut Lateral fold incorporate dorsal part of umbilical vessicle to the abdominal cavity as mid gut Tail fold incorporate dorsal part of umbilical vessicle to the abdominal cavity as hind gut P. 45 Failure in the esophagus length result in the stomach to be pulled upward and cause? The esophagus epithelium will proliferate and completely fill the lumen but the it will disappear this process is called recanalization. If it doesn't disappear it will cause esophageal atresia. P. 46 At first all part of the esophagus were smooth muscles put later on, in the proximal part the smooth muscles will be changed to skeletal muscles. Both the somatic and the autonomic part of the esophagus is innervated by vagus nerve. P.48 The most common cause of esophageal atresia is incomplete separation of esophagus from the latyngotracheal tube. P. 52 On the ventral border of the stomach there is ventral mesogastrium that attach to the anterior abdominal wall On the dorsal border of the stomach there is dorsal mesogastrium that attach to the posterior abdominal wall. P. 54 Dorsal mesentery is found on the left side and form celiac artery.
- 3. The ventral mesntery is fount on the right side and connect the stomach and duodenum. P. 56 Omental bursa is related to the rotation of the stomach. P. 62 Most part of ventral mesntery disappear except the upper part which forms hepatoduodanal ligament. P. 70 Ventral mesentery gives rise to hepato-gastric, hepato-duodenal and falciform ligament and attach the liver to anterior abdominal wall. P. 83 The mid gut has 3 parts:- cranial limb (small intestine), caudal limb( appendix and cecum) and ompahlocentric duct which connects with umbilical vesicle and then it disappears. P. 83 The mid gut rotates 90 degree counter clock wise and the cranial end (small intestine) moves to the right and the caudal end (cecum and appendix) moves to the left. Then after retraction the caudal end rotates 180 degree counterclockwise and moves back to the right bringing the cecum and appendix to the right lower quadrant. If there is incomplete rotation on the second round of rotation of caudal end, the cecum and appendix will be placed under the liver; subhepatic cecum and appendix. P. 87 At the first all organs of the GIT were intrapertonial P. 90 Ompalocele is failure to retract, failure for the midgut to go back to the abdomen. The intestine is located on the umbilical cord. Umbilical hernia is protrusion of the abdominal content mainly small intestine after retraction due to weak abdominalwall. Gastroschisis is ventral body wall, incomplete fusion of the left and right abdominal wall. And the intestine is not located on the umbilical cord rather pass lateral (to the right) of umbilical cord. P. 95 The small intestine should be placed in the central part after complet retraction.
- 4. P. 97 Mobile cecum is due to incomplete fixation of the ascending colon to the posterior abdominal wall. Which cause Volvulus. Internal hernia:- The small intestine may herniated to the mesentery. P. 102 The cloaca communicates with the umbilical vessicle by alantois. The urorectal septum divide the cloacal to ventral and dorsal part. The ventral part located anteriorly and forms urogential sinus which gives rise to urinary and gential organs. The dorsal part located posterior and forms the dorsal part of the rectum and anal cannal. P. 117 Anorectal agents is with fistula is due to failure of separation of the cloacla membrane. And there is abnormal communication b/n the rectum and bladder, rectum and vaginal. This causes passing of fecal matter through the vagina or through the ureter.