2.2 + 3.2 Gut development

Question 1

what makes up somatopleuric mesoderm? what does it form?

Answer 1

somatic mesoderm and ectoderm
forms body walls

Question 2

what makes up splanchnopleuric mesoderm? what does it form?

Answer 2

splanchnic mesoderm and endoderm
forms viscera

Question 3

parietal peritoneum is derived from…

Answer 3

somatic portion of lateral plate mesoderm

Question 4

visceral peritoneum is derived from…

Answer 4

splanchnic portion of lateral plate mesoderm

Question 5

what connects midgut to yolk sac?

Answer 5

vitelline duct

Question 6

2 closed ends of gut tube are called?

Answer 6

bucopharyngeal membrane
cloacal membrane

Question 7

when does bucopharyngeal membrane rupture? forms what?

Answer 7

4th week
mouth

Question 8

when does cloacal membrane rupture? forms what?

Answer 8

7th week
anus

Question 9

endoderm proliferates in the 5th week. what does this cause?

Answer 9

occludes lumen of gut tube temporarily, which reanalyses in 9th week

Question 10

which location of stomach grows more?

Answer 10

dorsal

Question 11

compare somatic and splanchnic pain

Answer 11

somatic- better localised

Question 12

what happens to liver and stomach on foregut rotation?

Answer 12

growth

Question 13

describe the normal bud development of pancreas

Answer 13

dorsal bud larger
ventral bud (from hepatic diverticulum, forced posteriorly and inferiorly)

fuse

Question 14

result of 2 pancreatic ducts not fusing properly

Answer 14

accessory pancreatic duct

Question 15

when does the intestinal loop elongate rapidly?

Answer 15

6th week

Question 16

what do the cranial and caudal parts of the intestinal loop become?

Answer 16

small intestine and large intestine

Question 17

how many rotations of midgut?

Answer 17

3x 90 degreee rotations clockwise

Question 18

when should intestinal loop return to a abdominal cavity?

Answer 18

10th week

Question 19

when should vitelline duct regress?

Answer 19

week 7

Question 20

vitelline duct function

Answer 20

connects midgut to developing yolk sac

Question 21

what’s a vitelline cyst?

Answer 21

patent middle section of vitelline duct

Question 22

problem caused by vitelline fistula

Answer 22

discharge of faecal material out of umbilicus possible

Question 23

rule of 2s for meckels diverticulum

Answer 23

-2% population
-located 2 feet proximal to ilio-caecal valve
-detected in under 2s
-2:1 male to female

Question 24

describe how the cloaca divides

Answer 24

-urorectal septum descends caudally in 4th-7th week
-forms urogenital sinus anteriorly, and anorectal sinus posteriorly
-cloacal membrane of anorectal septum ruptures in 7th week to open up to outside

Question 25

anal invagination forms the proctodeum. what is this made of?

Answer 25

ectoderm derived stratified squamous epithelia

Question 26

epithelia either side of pectinate line of anus

Answer 26

proximal- endoderm, columnar distal- ectoderm, stratified squamous

Question 27

epithelial difference either side of white line of anus

Answer 27

proximal- non keratinised distal- keratinised

Question 28

blood supply and pain type above and below pectinate line of anus

Answer 28

above- vague pain caused by stretch/chemical injury, gut blood supply below- localised pain (somatic), systemic blood supply

Question 29

what's anorectal agenesis

Answer 29

absence of anus

Question 30

handgun could form fistulae to which organs?

Answer 30

bladder, vagina