Embryology (02.13) Development of Digestive System Flashcards Preview

Anatomy (S2)(Unit 2) > Embryology (02.13) Development of Digestive System > Flashcards

Flashcards in Embryology (02.13) Development of Digestive System Deck (58)
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1
Q

the endoderm is composed of what two things?

A
  • epithelial lining

- glands of the GI tract

2
Q

during ____ ____ (week #___), endoderm from the dorsal portion of the ____ ___ is incorporated into the embryo, forming the innermost lining of the ____ ____ ____

A
  • body folding
  • yolk sac
  • week #4
  • primitive gut tube
3
Q

the fore gut forms during the ____ fold

A

head

4
Q

the hind gut forms during the ____ fold

A

tail

5
Q

during LATERAL folding, the yolk sac endoderm is incorporated as embryonic _____

A

midgut

6
Q

what 2 things compose the splanchnic mesoderm?

A
  • smooth m

- connective tissue of GI tract

7
Q

serous membrane lining abdominal cavity and organs

A

peritoneum

8
Q

a double layer of peritoneum that suspends an organ from the body wall (can contain CT, blood vessels, lymphatics, nerves)

A

mesentery

9
Q

peritoneum and mesoderm are both derived from the _____

A

mesoderm

10
Q

the ventral mesogastrium forms what 4 things?

A
  • lesser omentum
  • hepatogastric ligaments
  • hepoduodenal ligaments
  • falciform ligament
11
Q

the dorsal mesogastrium forms what?

A

greater omentum

12
Q

what is the ectoderm contribution to the GI tract?

A

neural crest

13
Q

neural crest cells (of the ectoderm) migrate into ____ of the GI tract to form the ____ ____ ____

A
  • walls

- enteric nervous system

14
Q

what is the arterial supply to the pharynx?

A

pharyngeal arch aa

15
Q

what is the arterial supply to the foregut?

A

celiac trunk

16
Q

what is the arterial supply to the midgut?

A

superior mesenteric a

17
Q

what is the arterial supply to the hind gut?

A

inferior mesenteric a

18
Q

what are the 9 derivatives of the foregut?

A
  • pharynx
  • lower respiratory system
  • esophagus
  • stomach
  • proximal 1/2 of duodenum (just after entrance of pancreatic and bile ducts)
  • liver
  • gall bladder
  • biliary system
  • pancreas
19
Q

at week #__, a ____ ____ appears on the VENTRAL side of the ____ ____ (will become the trachea, respiratory tree, and lungs)

A
  • 4
  • respiratory diverticulum
  • fore gut
20
Q

the stomach develops at week #__ and the greater curvature is on the ___ side and the lesser curvature is on the ___ side

A
  • # 4
  • dorsal
  • ventral
21
Q

the stomach undergoes a 90 degrees ____ rotation to have the lesser curvature on the ____ and the greater curvature on the _____

A
  • clockwise
  • right
  • left

*R and L vagus nn innervate accordingly

22
Q

as the stomach rotates, the ____ _____ is carried to the left. This enlarges the ____ ____ into a sizable recess between the ____ and ____ ____ ____

A
  • dorsal mesogastrium
  • omental bursa
  • stomach
  • posterior abdominal wall
23
Q

the distal 1/2 of the duodenum is in the ______ and therefore is supplied by the _____ ____ _____

A
  • midgut

- superior mesenteric a

24
Q

the fore gut and the midgut split at the ___ ___ ____

A

major duodenal pappilla

25
Q

bc the distal duodenum and the pancreas become pressed against the posterior abdominal wall as the stomach rotates and their mesenteries fuse with the parietal peritoneum, they are considered ____ ____

A

secondarily retroperitoneal

26
Q

the _____ _____ emerges ventrally from the endoderm of the distal ______ (week #__), grows superiorly toward septum transversum and gives rise to ____, ___ ___, and ___ ___

A
  • hepatic diverticulum
  • fore gut (week #4)
  • liver, gall bladder, and bile ducts
27
Q

the pancreas emerges from the distal fore gut as two ______ ____

A

endodermal buds

*dorsal bud and ventral bud

28
Q

what causes the fusing of the ventral and dorsal buds of the pancreas?

A

the rotation of the duodenum

29
Q

what two things does the ventral bud become?

A
  • uncinate process

- inferior portion of head of pancreas

30
Q

duct that is the distal portion of the bud duct and the ventral bud duct

A

main pancreatic duct

31
Q

duct that is the proximal dorsal bud duct

A

accessory pancreatic duct

32
Q

a(n) ____ ____ occurs with the ventral buds of the pancreas fail to fuse during rotation and wrap oppositely around the duodenum and fuse with each other, forming an ___ ____

A
  • annular pancreas

- obstructive ring

33
Q

what are the 6 derivatives of the midgut?

A
  • distal 1/2 of duodenum (just after major duodenal papilla)
  • jejunum
  • ileum
  • cecum and appendix
  • ascending colon
  • proximal 2/3 transverse colon
34
Q

what is the connection between midgut and yolk sac

A

vitalline duct

35
Q

what three things are in the cranial limb of the midgut?

A
  • distal duodenum
  • jejunum
  • proximal ileum
36
Q

what 4 things are in the caudal limb of the midgut?

A
  • distal ileum
  • cecum + appendix
  • ascending colon
  • proximal 2/3 transverse colon
37
Q

____ ____ in the abdominal cavity leads to temporary herniation of midgut loop into the proximal umbilical cord, causing ___ ____ ____

A
  • insufficient room
  • physiological umbilical hernia

*week 6-10

38
Q

a ____ _____ is a persisting umbilical hernia within the ____ umbilical cord

A
  • congential omphalocoele

- proximal

39
Q

congenital omphalocoeles are often associated with _____ malformations (chromosomal abnormalities) so mortality rates are _____

A
  • severe

- high

40
Q

_____ is a hernia of small intestine and occasionally other abdominal viscera through anterior body wall

A

gastrochisis

41
Q

gastrochisis does not involve the ____ ____ and exposure to ____ ____ can damage the viscera

A
  • umbilical cord

- amniotic fluid

42
Q

the first midgut rotation occurs at week ___ and is a ___ degree _______ rotation with the ____ ___ ___ being the center of the axis of rotation

A
  • 6
  • 90
  • counterclockwise rotation
  • SMA
43
Q

the second midgut rotation occurs at week ___ and is a ____ degree _____ rotation to bring the intestines into normal position

A
  • 10
  • 180
  • counterclockwise rotation
44
Q

the ascending and descending colon become ____ ____ due to their dorsal mesenteries being lost after fusing with the parietal peritoneum of the posterior abdominal wall

A

secondarily retroperitoneal

45
Q

what 4 structures are secondarily retroperitoneal?
(originally developed within the peritoneal cavity, but shifted into retroperitoneal position due to GI growth and rotation)

A
  • distal duodenum
  • pancreas
  • ascending colon
  • descending colon
46
Q

what 5 structures are intraperitoneal?

A
  • stomach
  • proximal duodenum
  • jejunum + ileum
  • transverse colon
  • sigmoid colon
47
Q

the caudal lime of the large intestine returns first and occupies the left side of the abdominal cavity, resulting in a ___-___ _____

A

left-sided colon

48
Q

_____ occurs when the there is an abnormal rotation of the midgut which may cause intestinal loop twist around mesenteric attachment site which can result in bowel obstruction or compromised blood flow

A

volvulus

49
Q

the abnormal narrowing of a lumen/orifice (tubular organ or structure)

A

stenosis

50
Q

the condition in which a body lumen or orifice is abnormally closed or absent

A

atresia

51
Q

an abnormal passageway between two organs/vessels or between an organ and the external environment

A

fistula

52
Q

intestines become temporarily occluded by epithelial cells at week __ but they should reanalyze by week __

A
  • 6

- 8

53
Q

_____ _____ is the most common GI malformation that occurs in 2-4% of the population with a ___ predominace

A
  • meckel’s (ideal) diverticulum

- male

54
Q

what five things are derivatives of the hind gut?

A
  • distal 1/3 of transverse colon
  • descending colon
  • sigmoid colon
  • rectum
  • superior portion of anal canal
55
Q

what two derivatives of the hind gut are derived from the posterior portion of the cloaca after it is partitioned by the urorectal septum?

A
  • rectum

- superior portion of anal canal

56
Q

in the hind gut, the ____ ____ grows inferiorly toward the cloacal membrane dividing it into urogential and anal membranes and partitioning the ____ and the ____ ____ (ventrally) and the ___ _____ (dorsally)

A
  • urorectal septum
  • cloaca
  • urogenital sinus
  • anorectal canal
57
Q

hind gut fistulas can result if the urorectal septum fails to completely separate the hind gut from the ____ ____ or if the cloaca is too _____

A
  • urogenital septum

- small

58
Q

____ ____ affects variable portions of the bowel where the neural crest cells fail to migrate to form the enteric nervous system
-the a ganglionic portion constricts, bowel distends proximal to constriction, can lead to severe constipation/ failure to thrive

A

hirschsprung’s disease (a ganglionic megacolon)