Digestive Development 2

Question 0

How does the midgut communicate with the yolk sac in early development

Answer 0

Vitelline duct

Question 1

What artery supplies the midgut?

Answer 1

Superior mesenteric

Question 2

When the midgut and its mesentery rapidly expands, particularly cephalopod end, what does structure does this cause to develop?

Answer 2

Primary intestinal loop

Question 3

Because the intestines grow too big for the body cavity, what happens?

Answer 3

They temporarily herniate outside the body cavity into the umbilical cord and then return

Question 4

How does the primary intestinal loop rotate?

Answer 4

Around the axis of the superior mesenteric artery about 270*

Question 5

When do the intestines return to the body?

Answer 5

10th week

Question 6

What appears on the cecal bud as the intestines are coming back into the body?

Answer 6

Appendix

Question 7

The appendix develops while the cecum is descending so what is its most common position?

Answer 7

Retro colic

Retrocecal

Question 8

What is the cloaca?

Answer 8

Endoderm lined cavity that is covered at the ventral boundary by ectoderm (forms cloacal membrane)

Question 9

What happens when the cloacal membrane ruptures?

Answer 9

7th week - opening to the hind gut forms

Question 10

What’s the blood supply and derivatives and mucosa of the upper end of the anal canal?

Answer 10

Superior rectal arteries (branch of superior mesenteric)
Endoderm
Simple columnar epithelium

Question 11

What’s the blood supply and derivatives and mucosa of the lower end of the anal canal?

Answer 11

Inferior rectal arteries (branch of internal pudendal)
Ectoderm
Stratified squamous epithelium

Question 12

What is the dividing line between upper anal canal and lower anal canal?

Answer 12

Pectinate line

Question 13

What’s gastroschisis

Answer 13

Herniation of the bowels lateral to the umbilicus not contained in the umbilical cord

Question 14

What can increase the chances of gastroschisis occuring?

Answer 14

Cocaine use

But NOT chromosomal abnormalities

Question 15

What can be detected in amniotic fluid that is elevated with gastroschisis

Answer 15

Alpha fetoprotein

Question 16

What is omphalocele

Answer 16

Herniation of the abdominal viscera through an enlarged umbilical ring covered by the amnion

Question 17

Omphalocele is highly associated with what?

Answer 17

Chromosomal abnormalities

Question 18

What is meckels diverticulum?

Answer 18

A remnant of the Vitelline duct found on the ileum by the umbilicus

Question 19

Is meckels diverticulum clinically significant?

Answer 19

Only if it contains heterotopic pancreatic tissue or gastric mucosa

Question 20

What is a gut atresia

Answer 20

Congenital absence of an opening or lumen

Question 21

What is a gut stenosis

Answer 21

Narrowing of the gut orifices or openings

Question 22

Where do most gut stenosis and atresias occur?

Answer 22

In the duodenum because it’s closed off and recanalized

Question 23

What cause rectourethral and rectovaginal fistulas

Answer 23

Abnormalities in formation of the cloaca and/or the urorectal septum

Question 24

What causes rectoanal atresias

Answer 24

Vascular accidents

Question 25

What’s an imperforate anus?

Answer 25

When the cloacal membrane fails to break down