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Flashcards in Digestive Development 2 Deck (26):
0

What artery supplies the midgut?

Superior mesenteric

1

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

Vitelline duct

2

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

Primary intestinal loop

3

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

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

4

How does the primary intestinal loop rotate?

Around the axis of the superior mesenteric artery about 270*

5

When do the intestines return to the body?

10th week

6

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

Appendix

7

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

Retro colic
Retrocecal

8

What is the cloaca?

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

9

What happens when the cloacal membrane ruptures?

7th week - opening to the hind gut forms

10

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

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

11

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

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

12

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

Pectinate line

13

What's gastroschisis

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

14

What can increase the chances of gastroschisis occuring?

Cocaine use
But NOT chromosomal abnormalities

15

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

Alpha fetoprotein

16

What is omphalocele

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

17

Omphalocele is highly associated with what?

Chromosomal abnormalities

18

What is meckels diverticulum?

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

19

Is meckels diverticulum clinically significant?

Only if it contains heterotopic pancreatic tissue or gastric mucosa

20

What is a gut atresia

Congenital absence of an opening or lumen

21

What is a gut stenosis

Narrowing of the gut orifices or openings

22

Where do most gut stenosis and atresias occur?

In the duodenum because it's closed off and recanalized

23

What cause rectourethral and rectovaginal fistulas

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

24

What causes rectoanal atresias

Vascular accidents

25

What's an imperforate anus?

When the cloacal membrane fails to break down