Development Of The Gut

Question 1

The gut tube forms as a result of the lateral, cranial and caudal body ______ that lead to the internalization of the ______ portion of the endodermal _____ ____ to become an ______ lined tube within the embryo (3rd to 4th week)

Answer 1

The gut tube forms as a result of the lateral, cranial and caudal body folds that lead to the internalization of the dorsal portion of the endodermal yolk sac to become an endoderm lined tube within the embryo (3rd to 4th week)

Question 2

The fetal gut tube communicates with the yolk sac via _____ ____. Failure of this structure to obliterate can result in a ______ _____. Incomplete closure of this structure can cause a ______ ____, _____ ____, or a _____ _____.

Answer 2

The fetal gut tube communicates with the yolk sac via VITELLINE DUCT. Failure of this structure to obliterate can result in a VITELLINE FISTULA. Incomplete closure of this structure can cause a VITELLINE CYST, VITELLINE SINUS, or a MECKEL’S DIVERTICULUM.

Question 3

Meckel’s diverticulum is found on the ____, and when ectopic tissue is present, it’s often _____-secreting ______ mucosa.

Answer 3

Meckel’s diverticulum is found on the ILEUM, and when ectopic tissue is present, it’s often HCL-secreting GASTRIC mucosa.

Question 4

If the lateral body folds do not completely met and fuse correctly, there may be a weakness of _____ ____ ____ which may lead to _______.

Answer 4

If the lateral body folds do not completely met and fuse correctly, there may be a weakness of ANTERIOR ABDOMINAL WALL which may lead to GASTROSCHISIS.

Question 5

Failure to recanalize the gut tube leads to ______. This occurs most commonly in the _______. Presence of bile in vomitus will indicate that the obstruction is ____ to the entry of the common bile duct.

Answer 5

Failure to recanalize the gut tube leads to ATRESIA. This occurs most commonly in the DUODENUM. Presence of bile in vomitus will indicate that the obstruction is DISTAL to the entry of the common bile duct.

Question 6

Abnormalities in the formation of the respiratory diverticulum may result in _______ _____ (which subsequently leads to ________), ______ _____, or _____ ______.

Answer 6

Abnormalities in the formation of the respiratory diverticulum may result in ESOPHAGEAL ATRESIA (which subsequently leads to POLYHYDRAMNIOS), ESOPHAGEAL STENOSIS, or TRACEHOESOPHAGEAL FISTULA.

Question 7

Foregut gives rise to _____, ____, and first _____ of ______.

Answer 7

Foregut gives rise to ESOPHAGUS, STOMACH, and first HALF of DUODENUM.

Question 8

Evaginations of the foregut give rise to _____, ____ ____, and ________. Supplied by ____ ____ and ____ ____.

Answer 8

Evaginations of the foregut give rise to LIVER, GALL BLADDER, and PANCREAS. Supplied by CELIAC TRUNK and VAGUS NERVE.

Question 9

The midgut gives rise to the ____ ____ _____, ______, _____, ______, _____, ______ _____, ______ ___ _______. All of these structures are supplied by ______ ____ ___ and ___ ____.

Answer 9

The midgut gives rise to the DISTAL 1/2 OF DUODENUM, JEJUNUM, ILEUM, CECUM, APPENDIX, ASCENDING COLON, PROXIMAL 2/3 OF TRANSVERSE COLON. All of these structures are supplied by SUPERIOR MESENTERIC ARTERY and VAGUS NERVE.

Question 10

The hindgut gives rise to _____ ___ _____ ______, _____ _____, ____ _____, _____, and ______ _____ ____. Supplied by _____ _____ ___ and ____ _______ _____.

Answer 10

The hindgut gives rise to DISTAL 1/3 OF TRANSVERSE COLON, DESCENDING COLON, SIGMOID COLON, RECTUM, and UPPER ANAL CANAL. Supplied by INFERIOR MESENTERIC ARTERY and PELVIC SPLANCHNIC NERVES.

Question 11

Endoderm gives rise only to the ______ of the gut tube, ________ of the gut tube derivatives (e.g. _______ of the gall bladder) and glands derived from the _______ (e.g. intestinal glands). The other layers of the gut tube organs (e.g. smooth muscle, connective tissue) are derived from ______ ______.

Answer 11

Endoderm gives rise only to the epithelium of the gut tube, epithelium of the gut tube derivatives (e.g. epithelium of the gall bladder) and glands derived from the epithelium (e.g. intestinal glands). The other layers of the gut tube organs (e.g. smooth muscle, connective tissue) are derived from splanchnic mesoderm.

Question 12

The only vessel to traverse the ventral mesentery is the _____ _____, and the adult remnant of this is the _____ ____. The adult mesenteries derived from this mesentery are ____ ____, and ____ _____. Everything else is derived from dorsal.

Answer 12

The only vessel to traverse the ventral mesentery is the UMBILICAL VEIN, and the adult remnant of this is the LIGAMENTUM TERES. The adult mesenteries derived from this mesentery are FALCIFORM LIGAMENT, and LESSER OMENTUM. Everything else is derived from dorsal.

Question 13

The hepatic diverticulum evaginates from the _____ lining of the ______ wall of the gut tube in the region of the ____ portion of the duodenum. The site of this diverticulum marks the termination of the _____. The diverticulum enters the _____ mesentery. The distal end of the diverticulum becomes the ____ and _____ ______, the proximal part becomes the _____ _____ ______.

Answer 13

The hepatic diverticulum evaginates from the endodermal lining of the ventral wall of the gut tube in the region of the 2nd portion of the duodenum. The site of this diverticulum marks the termination of the foregut. The diverticulum enters the ventral mesentery. The distal end of the diverticulum becomes the liver and gall bladder, the proximal part becomes the biliary duct system.

Question 14

The _____ _____ exit the liver and enter the _____ through the bare area. The bare area is surrounded by the _____ ____, which is the reflection of peritoneum from visceral peritoneum of the liver onto parietal peritoneum on the diaphragm.

Answer 14

The HEPATIC VEINS exit the liver and enter the IVC through the bare area. The bare area is surrounded by the CORONARY LIGAMENT, which is the reflection of peritoneum from visceral peritoneum of the liver onto parietal peritoneum on the diaphragm.

Question 15

The pancreas develops from two pancreatic diverticula (buds) which evaginate from the ______ lining of the gut tube in the region of the ____ portion of the duodenum. The two pancreatic buds fuse together to form a single pancreas but retain two separate ducts which enter the gut tube. The ventral bud gives rise to the _____ pancreatic duct (of _____) and the lower portion of the _____ of the pancreas and the ______ _____. The dorsal pancreatic bud gives rise to the ______ pancreatic duct (of ______) and the upper portion of the _____ of the pancreas and the _____, ____ and _____ of the pancreas

Answer 15

The pancreas develops from two pancreatic diverticula (buds) which evaginate from the endodermal lining of the gut tube in the region of the 2nd portion of the duodenum. The two pancreatic buds fuse together to form a single pancreas but retain two separate ducts which enter the gut tube. The ventral bud gives rise to the major pancreatic duct (of Wirsung) and the lower portion of the head of the pancreas and the uncinate process. The dorsal pancreatic bud gives rise to the minor pancreatic duct (of Santorini) and the upper portion of the head of the pancreas and the neck, body and tail of the pancreas

Question 16

Clinical consequence of anular pancreas

Answer 16

Bowel obstruction

Question 17

The spleen develops in the _____ mesentery of the _____ (_____ _______). The mesentery covering the spleen becomes the _____ peritoneum of the spleen. The mesentery between the spleen and the gut tube becomes the ________ _______. The mesentery between the spleen and the dorsal body wall becomes the ___________ ________ (most of which subsequently fuses to become ______ peritoneum). The blood supply to the spleen (the splenic artery) reaches the spleen by passing within the _______ ________.

Answer 17

The spleen develops in the dorsal mesentery of the stomach (dorsal mesogastrium). The mesentery covering the spleen becomes the visceral peritoneum of the spleen. The mesentery between the spleen and the gut tube becomes the gastrosplenic ligament. The mesentery between the spleen and the dorsal body wall becomes the splenorenal ligament (most of which subsequently fuses to become parietal peritoneum). The blood supply to the spleen (the splenic artery) reaches the spleen by passing within the splenorenal ligament.

Question 18

Major peritoneal organs:
______, ____, ____ _____, ____, beginning of _______, ____ of pancreas, ______, ______, _______, ______ _____, _____ _____.

Answer 18

Major peritoneal organs:
STOMACH, LIVER, GALL BLADDER, SPLEEN, BEGINNING OF DUODENUM, TAIL OF PANCREAS, JEJUNM, ILEUM, APPENDIX, TRANSVERSE COLON, SIGMOID COLON

Question 19

Major secondary retroperitoneal organs:
Most of ______, most of _____, _____ _____, _____ _____, and ____ ______. The peritoneum that covers these organs are ____ ____.

Answer 19

Major secondary retroperitoneal organs:
Most of DUODENUM, most of PANCREAS, ASCENDING COLON, DESCENDING COLON, and UPPER RECTUM. The peritoneum that covers these organs are PARIETAL PERITONEUM.

Question 20

Major primary retroperitoneal organs:

_____, ____ ___, _____, _____, ____, ____ ____, ___ ___

Answer 20

Major primary retroperitoneal organs:

KIDNEY, ADRENAL GLAND, URETER, AORTA, IVC, LOWER RECTUM, ANAL CANAL

Question 21

In omphalocele, the abdominal organs are within the _____ ____ and separated from _____ ____. With gastrochisis, the abdominal organs are outside the _____ ____ and exposed to ____ ____.

Answer 21

In omphalocele, the abdominal organs are within the UMBILICAL CORD and separated from AMNIOTIC FLUID. With gastrochisis, the abdominal organs are outside the UMBILICAL CORD and exposed to AMNIOTIC FLUID.