Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

(OMS1) GIGU Exam > Lecture 10: Development of the GI system > Flashcards

Lecture 10: Development of the GI system Flashcards

1
Q

Describe the development of the primitive gut (include days)

A
  • Yolk sac and endodermal sheet precursor (day 20)
  • Branches forming Foregut, midgut and hindgut forms from the sheet (day 24)
  • branch to yolk sac also narrows and forms the vitelline duct (day 26)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What arteries are associated with the primitive gut?

A

Foregut - celiac trunk
midgut - SMA
hindgut - IMA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What organs come from the foregut?

A

Esophagus, stomach, liver, gallbladder, pancreas, upper duodenum (upper organs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What organs come from the midgut?

A

most of the small intestines, ascending colon and proximal 2/3 of the transverse colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What organs come from the hindgut?

A

distal 1/3 of transverse colon to anal canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What parts of the GI tract/tube come from the endoderm?

A

mucosal epithelium and GI glands (except for lower 1/3 of anus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What parts of the GI tract/tube comes from the splanchnic mesoderm?

A

Muscles, vessels and Ct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What parts of the GI tract/tube comes from the ectoderm?

A

ENS ganglia and nerves (NCC derived)

Epithelium of lower 1/3 of anus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When do the dorsal and ventral mesenteries develop?

A

Wk 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What structures come from the dorsal mesentery (posterior wall connector)?

A 
greater orementum (gastrosplenic, gastrocolic and splenorenal ligaments)
small intestine mesentery
Mesoappendix
transverse mesocolon
sigmoid mesocolon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What structures come from the ventral mesentery (anterior wall connector)?

A

lesser omentum -hepatoduodenal and hepatogastric ligaments, basically all the liver ligaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does intraperitoneal mean?
What does retroperitoneal mean?
What does secondary retroperitoneal mean?

A
  • suspended by mesentery
  • fused with the abdominal wall
  • organs initially suspended by mesentery but has since fused with body wall
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the process of stomach rotation

Vagus innervation?

A

-Starts as a tube facing anteriorly, then rotates 90 to the left as dorsal mesogastrum enlarges leftward to form the greater omentum

-Ventral stomach on the left side (L. vagus n.)
Dorsal stomach on the right side (R. vagus n.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Hypertrophic Pyloric Stenosis
Cause
Clinical

A
  • NCC did not properly migrate so ENS not fully populated > missing ENS control of the sphincter so it cannot relax
  • pyloric lumen narrowing causing obstruction of food passage, projectile vomiting, few BM, cannot gain weight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe how the liver develops and when does this happen?

A

Primitive gut endoderm develops the hepatic diverticulum > differentiation into hepatocytes/bile ducts and hepatic ducts (main liver) + gallbladder

Week 4-5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The splanchnic mesoderm of the primitive gut develops into which cells of the liver?

A

stromal, Kupffer and stellate cells

17
Q

Describe how the pancreas develop and when does this happen?

A

-primitive gut develops the dorsal pancreatic bud and ventral pancreatic duct which grow into respective mesentery > dorsal and ventral buds fuse at wk 5

Day 30 - 35 (week 5)

18
Q

Dorsal pancreas includes which parts?

Ventral pancreas includes which parts?

A
  • head, body and tail of pancreas

- uncinate process

19
Q

Annular pancreas

A

duodenal obstruction or stenosis

bilious vomitin if annulus is in the inferior bile duct, low birth weight

20
Q

What are some anomalies in pancreatic development?

A 
Accessory pancreatic duct
Pancreas divisum (separated ducts, single pancreatic duct did not form - prone to pancreatitis)
21
Q

How does the gallbladder form?

How does the bile duct form?

A
  • ventral cystic diverticulum forms at Wk 5 and forms the gallbladder
  • liver develops a closed bile duct that is reopened by reacanalization
22
Q

Biliary atresia
Cause
Symptoms

A
  • obliterated exta/intrahepatic ducts and are replaced by fibrotic tissues due to inflammation
  • neonatal jaundice, white stool, dark urine, can be treated with liver transplant
23
Q

How does the spleen develop and when does this happen?

A

Wk 4: mesenchyme condenses in the dorsal mesogastrium

Wk 5: spleen forms (mesoderm, not endoderm)

24
Q

What is special about the development of the midgut?

A

Abdomen has limited size, so midgut herniates into the umbilicus as it lengthens between and returns back (Wk 10/Day 73)

25
Q

Describe how gut (intestines) rotation occurs and when doe these happen?

A

Day 50: gut rotates CCW at 90 degrees > cecum and ascending colon end up on the left

Day 70: gut rotates CCW at 180 degrees > cecum at RUQ and ascending colon is anterior to duodenum

Day 77: Midgut returns back from herniation > cecum goes back to RLQ and ascending colon is dragged to the right abdomen

26
Q

What are the retroperitoneal viscera at the end of GI development?

What are the secondary retroperitoneal viscera at the end of GI development?

A
  • thoracic esophagus and rectum (entrance and exit)
  • duodenum, pancreas, ascending and descending colon
  • everything else is intraperitoneal
27
Q

Omphalocele

A

-wall weakness after lateral body folding, allowing bowel to herniate through umbilicus with peritoneal covering
usually associated with Trisomy 13 or 18

28
Q

Gastroschisis

A

abdominal wall herniation with no peritoneal covering

29
Q

Meckel’s diverticulum
Cause
Clinical

A
  • vitelline duct did not regress, leading to a pouch in the lower small intestine
  • abdominal swelling, SB obstruction, sepsis, Gi bleeding
30
Q

Non-rotation of midgut loop

Reverse gut rotation

A

-2nd CCW 180 rotation did not occur
left sided colon and right sided small intestines

-2nd 180 rotation is CW instead of CCW
transverse colon is behind duodenum

31
Q

Volvulus

A
  • rolled up twisted intestines

- acute AP, vomiting, GI bleed

32
Q

Intestinal Stenosis and Atresia

A
  • caused by ineffective recanalization (stenosis for partial obstruction, atresia for complete obstruction)
  • commonly associated with Trisomy 21
33
Q

Describe the fate of the cloaca (distal hindgut)

A

Urorectal septum develops infoldings that separate dorsal anorectal canal and ventral urogenital sinus
-cloacal membrane ruptures creating the exterior canal

34
Q

Describe the development of the anal canal and the pectineal line

A

-anal rectal lumen has epithelial plug that closes it off > mesenchyme forms anal pit with ectodermal walls > apoptosis eventually opens the plug

Superior 2/3 of anal canal: endoderm
Inferior 1/3 of anal canal: ectoderm

(these 2 are divided by the pectineal line)

35
Q

Imperforated anus

A

Persistent anal membrane

(OMS1) GIGU Exam (40 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions