Histology - GI Development

Question 1

Liver, Gall Blader, and ventral part of pancreas derived from

Answer 1

Ventral Bud

Question 1

Omphalocele

Answer 1

no umbilical hernia reduction, mass may include foregut structures, high rate of mortality

Question 2

RA high Caudally

Answer 2

RA Concentration Gradient

Question 2

Hypertrophic pyloric stenosis

Answer 2

Smooth muscle hypertrophy/hyperplasia

Question 3

ilial diverticulum. ~2% of population, ~2 inches long, ~2 feet from ileocecal junction

Answer 3

2X2X2 rule

Question 4

270 degree purpose

Answer 4

Places small intestin within loop of large intestine

Question 6

not gut tube. From Visceral Mesoderm, intraperitoneal.

Answer 6

Spleen derivation

Question 7

Biliary duct atresia

Answer 7

Failure of duct to recanalize. Intrahepatic: generally fatal, Extrahepatic: often correctable

Question 7

Annular pancreas

Answer 7

Ventral bud encircles the duodenum. May constrict/occlude duodenum.

Question 7

Colorectoanal atresia

Answer 7

imperforate anus

Question 9

rectum & proximal anus

Answer 9

Anorectal canal

Question 10

Midgut developmental events

Answer 10

Week 5 - Week 12. Physiological umbilical herniation, 270 degree counterclockwise rotation, differential growth

Question 11

Pancrease source

Answer 11

Dorsal Pancreatic Bud

Question 13

prolifertation of epithelium that closes the lumen. Completes by week 5

Answer 13

Occlusion

Question 14

SHH & HOX

Answer 14

Concentric layering of the gut tube

Question 15

Distal anus derived from

Answer 15

ectoderm, separated by pectinate line

Question 16

malrotation

Answer 16

Left-sided colon, reverse intestinal rotation

Question 17

90 CCW rotation only

Answer 17

Left-sided colon

Question 18

greater omentum

Answer 18

Dorsal mesogastrium - bloody supply

Question 18

Physiological umbilical herniation purpose

Answer 18

Accomodates expanding liver & gut tube

Question 19

Reversed intestinal rotation

Answer 19

90 CCW, 180 CW - places large colonbehind duodenum.

Question 20

Jejunal, ileal stenoses/atresia

Answer 20

Ischemic necrosis, herniation, volvulus (twisting)

Question 21

Connects intestinal loop to yolk sac

Answer 21

Vitelline duct

Question 22

Growth induced reopening of the lumen - completes by week 9

Answer 22

Recanalization

Question 24

hindgut fistulas

Answer 24

Rectoperineal fistula, Colovaginal (rectovaginal) fistula, Colovesical (urorectal) fistula

Question 25

falciform ligament & lesser omentum

Answer 25

Ventral mesogastrium - liver budding, ends at umbilicus

Question 26

RA & HOX

Answer 26

Cephalocaudal differentiation

Question 27

SHH High in Lumen

Answer 27

SHH Concentration Gradient

Question 28

Remnant of vitelline duct, generally asymptomatic, but may present like appendicitis.

Answer 28

ileal (Meckel’s) diverticulum

Question 30

Urorectal septum forms

Answer 30

dividing cloaca into anorectal canal and urogenital sinus.

Question 31

Esophageal, gastric, duodenal stenoses/atresias

Answer 31

Improper recanalization - epithelial issue

Question 32

hernia due to anterior body wall defect, mass not within umbilicus, lower mortality

Answer 32

Gastroschisis