Development Of Gut And Mesenteries

Front 1

explain the establishment of the gastric curvatures

Back 1

gastric curvatures arise because of rotations of the stomach and differential growth

Front 2

walk us through the stomach rotations

Back 2

1) stomach rotates 90 on longitudinal axis
2) clockwise rotation around anterior-posterior axis (pulls stomach up)

Front 3

walk us through the formation of the greater and lesser curvatures

Back 3

1) greater curvature comes because of faster left side
2) lesser curvature arises because of slower growing right side

Front 4

walk us through the formation of the greater omentum and lesser omentum

Back 4

1)dorsal megogastrium is pulled to left with first 90* lateral rotation
2)ventral megagastrium is pulled to the right and becomes lesser omentum

Front 5

how does the omental bursa form?

Back 5

the omental bursa forms when dorsal mesogastrium is pulled to the left
it basically forms a space behind the stomach

Front 6

what is the author embyrology related name for the lesser curvature vs greater curvature?

Back 6

greater curvature - dorsal mesogastrium
lesser curvature - ventral mesogastrium

Front 7

where does the left and right vagus end up?

Back 7

left vagus ends up on anterior wall
right vagus ends up on posterior wall

Front 8

What is the relationship between the liver and the ventral mesogastrium?

Back 8

ventral mesogastrium attaches to the liver and faliciform ligament when it gets pulled to the right with the longitudinal rotation

Front 9

what is the hepatic diverticulum?

Back 9

ventral outgrowth of endodermal epithelium at caudal end of foregut

Front 10

What is the relationship between the hepatic diverticulum and the umbilical and vitulline blood vessels

Back 10

diverticular strands intermingle with veins and septum transversum

Front 11

How does the bile duct form?

Back 11

a connection persists between the hepatic diverticulum and the foregut

Front 12

What forms the cystic duct and the gall bladder?

Back 12

secondary diverticulum on ventral side of bile duct becomes cystic duct and gallbladder

Front 13

What are the steps of liver development?

Back 13

1) formation of hepatic diverticulum from endothelium of foregut
2)formation of hepatic duct
3) formation of cystic duct and gallbladder
4) continued growth by caudal enlargement into ventral mesogastrium

Front 14

Where does the pancreatic diverticuli originate from?

Back 14

two pancreatic diverticuli, dorsal and ventral originate from evaginations of distan foregut endoderm (near the hepatic diverticulum)

Front 15

What happens when the pancreatic diverticuli fuse?

Back 15

dorsal diverticulum becomes upper part of pancreas
ventral diverticulum becomes the lower part of pancreas

Front 16

What forms the common duct of Warsung?

Back 16

distal portion of dorsal duct

Front 17

What becomes the Acessory Duct of Santorini?

Back 17

proximal portion of dorsal duct

Front 18

when does the liver take over hemopoeitic function of the yolk sac?

Back 18

2 - 7th month of development

Front 19

What forms from the dorsal diverticulum?

Back 19

upper half of head
isthmus
body
tail

Front 20

what forms from the ventral pancreatic diverticuli?

Back 20

lower half of head

Front 21

What goes on in general with the midgut?

Back 21

1) rapid elongation forms 2 limbs of a loop
2) physiological umbilical herniation
3) rotation along superior mesenteric artery axis
4) herniated loops return
5)fixation in dorsal mesentery or body wall

Front 22

When does the physiological herniation occur

Back 22

6 weeks

Front 23

What are the boundaries of the two limbs of the primary intestinal loop?

Back 23

cephalic - foregut junction to vitelline duct
caudal - vitelline duct to hindgut

Front 24

What rotations occur to the primary intestinal loop?

Back 24

1) counterclockwise of 180 puts caudal limb above cephalic limb
2) another counterclockwise 90* rotation so now cecum is on the side

Front 25

What forms from the cephalic limb of the intestinal loop? mneumonic

Back 25

DMJ

Front 26

what forms from the cephalic limb of the intestinal loop

Back 26

duodenum, distal half
jejunum
major proximal part of ileum

Front 27

what happens to the caudal limb of the intestinal loop?

Back 27

distal ileum
cecum
appendix
ascending colon
proximal 2/3 of transverse colon

Front 28

What is the name for portion of the vitelline duct persisting?

Back 28

Mecke's diverticulum

Front 29

How does the midgut derivatives get fixed to body wall?

Back 29

mesoduodenum fuses with body wall
mesentery of ascending colon fuses with body wall

Front 30

What happens to the mesentery proer? (3)

Back 30

it persists throughout life
it gets branches of the superior mesentery artery
it goes from upper left to lower right

Front 31

what happens to the transverse mesocolon?

Back 31

it persisits

Front 32

What happens to the mesoappenxis?

Back 32

it persists

Front 33

What are the borders of the hindgut?

Back 33

posterior inestinal portal to cloacal membrane

Front 34

What is the allantois?

Back 34

diverticulation from ventral floor of hindgut into umbilicus

Front 35

What is the urorectal septum?

Back 35

superior angle between hindgut and allantois growign caudally towards cloacal membrane

Front 36

What divides the terminal hindgut into ventral and dorsal portions?

Back 36

urorectal septum

Front 37

what does the ventral portion of the terminal hindgut become?

Back 37

urogenital sinus

Front 38

What does the dorsal portion of the hindgut become?

Back 38

rectum

Front 39

what divides the cloacal membrane into two?

Back 39

urogenital septum

Front 40

what two portions does the cloacal membrane get divided into?

Back 40

anal membrane
urethral membrane

Front 41

what is the proctoderm?

Back 41

ectodermal depression where anal membrane lies

Front 42

When does the anal membrane rupture

Back 42

week 9

Front 43

when does the urorectal septum reach the cloacal membrane

Back 43

week 7

Front 44

what are the surrondings around the anal membrane called?

Back 44

anal folds

Front 45

what are the main parts of the hindgut? &7)

Back 45

ascending colon
sigmoid colon
allantois
urorectal septum
rectum
anal membrane
urethral membrane

Front 46

what does the hindgut from from?

Back 46

ectoderm

Front 47

how does the esophagus form?

Back 47

1) respiratory/tracheobronchial diverticulum grow from ventral foregut distal to pharynx
2) esophagotracheal septum seperates esophagus from respiratory diverticulum
2) esophagus lengths during descent of heart and lung

Front 48

when does the esophagus seperate from the respiratory diverticlum

Back 48

week 4