Embryology of the GI Tract Flashcards Preview

Alimentary System > Embryology of the GI Tract > Flashcards

Flashcards in Embryology of the GI Tract Deck (23):
1

What is gastrulation?

The formative process by which the 3 germs layers and axial orientation of the embryo is established

2

What are the 3 germ layers?

Ectoderm, endoderm, mesoderm

3

During what week of development is the primordial gut formed?

4th

4

From what part of the primal gut tube does the foregut develop?

The cranial part

5

The laryngo-tracheal diverticulum develops from what?

The ventral wall of the foregut

6

What does the trachea-oesophageal septum divide the foregut into?

Trachea and oesophagus

7

From what parts of the foregut and midgut is the duodenum formed?

The caudal part of the foregut and the cranial part of the midgut

8

During what week of development does the liver primordium appear?

Middle of the third week

9

What is formed by ventral outgrowth from the bile duct during development?

The gall bladder and cystic duct

10

During what week of development are the pancreas and spleen formed?

5th

11

The development of what part of the GI tract involves the rapid elongation of the gut-tube and its associated mesentery?

Midgut

12

What part of the primary intestinal loop will become the distal duodenum, jejunum and proximal ileum?

The cephalic part

13

The caudal part of the primary intestinal loop will become what structures?

Distal ileum, caecum, appendix, ascending colon and proximal 2/3 of the transverse colon

14

What structures are part of the hindgut?

Distal 1/3 of transverse colon, descending colon, sigmoid colon, rectum and upper part of anal canal

15

The endoderm of the handgun forms

lining of bladder and urethra

16

Give a disease of the oesophagus that can arise from abnormal development

Oesophageal atresia
Trachea-oesophageal fistula

17

What causes incomplete separation of the laryngo-tracheal tube?

Incorrect deviation of the trachea-oesophageal septum

18

What may arise from abnormal development of the pancreas and cause duodenal stenosis?

Annular pancreas

19

What is an omphalocele?

Herniation of the abdominal viscera through the umbilicus

20

What might cause an omphalocele?

Failure of retraction of the herniated loops - liver, stomach or intestinal loops

21

What is gastroschisis?

Herniation of the abdominal contents directly through the body wall into the amniotic cavity

22

What can be formed by remnants of the Vitelline duct and what can it cause?

Meckel's diverticulum
May form fistula or vitalline cyst/ligament

23

What might result from the incomplete separation of the hindgut from the urogenital sinus by the urorectal septum?

Urorectal fistula
Rectovaginal fistula
Rectoanal atresia
Imperforate anus