Embryology

Question 1

What is the first phase of embryo development?

Answer 1

Growth/proliferation

Question 2

What is the second phase of embryo development?

Answer 2

Morphogenesis

Question 3

What is the third phase of embryo development?

Answer 3

Differentiation

Question 4

The cranial part of the primitive gut tube forms

Answer 4

The oesophagus

Question 5

Laryngotracheal diverticulum

Answer 5

Develops from the ventral wall of the foregut, forms lung bud

Question 6

Tracheoesophageal septum

Answer 6

Divides the foregut tube into trachea and oesophagus

Question 7

What happens when the tracheoesophageal septum deviates incorrectly?

Answer 7

Incomplete separation of laryngotracheal tube resulting in oesophageal atresia and tracheoesophageal fistula

Question 8

How many times does the stomach rotate in the developing embryo?

Answer 8

Twice
90 degree rotation around its own longitudinal axis
Anterio-posterior axis rotation

Question 9

In what week does the foregut dilate to form the stomach?

Answer 9

4th week

Question 10

What creates the lesser sac?

Answer 10

The longitudinal rotation of the stomach pulls the dorsal mesentery to the left

Question 11

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

Answer 11

The duodenum

Question 12

What causes the duodenum to be C shaped?

Answer 12

The rotation of the stomach along the anterio-posterior axis

Question 13

The outgrowth of endoderm in the distal foregut forms which bud?

Answer 13

Liver bud (hepatic diverticulum)

Question 14

The connection between the liver bud and the duodenum narrows to form

Answer 14

The bile duct

Question 15

The gallbladder and the cystic duct are formed from

Answer 15

The ventral outgrowth from the bile duct

Question 16

What forms the spleen in week 5?

Answer 16

Differentiation of a mesenchymal condensation in the dorsal mesogstrium from end of week 4

Question 17

Spleen acts as a haematopoietic organ until

Answer 17

Week 14

Question 18

What happens to the spleen during weeks 15-17?

Answer 18

Acquires its lobular shape and is colonised by T-lymphocytes

Question 19

After week 23 the spleen starts its lymphoid function due to

Answer 19

The arrival of B-cell precursors

Question 20

How many buds form the pancreas?

Answer 20

2, grow from endodermal lining of the duodenum

Question 21

The ventral bud froms

Answer 21

The uncinate process and inferior part of the head of the pancreas

Question 22

Main pancreatic duct formed from

Answer 22

Ventral duct plus distal part of the dorsal duct

Question 23

In what week does rotation of the midgut begin?

Answer 23

Week 6

Question 24

Why does the gut tube herniate?

Answer 24

Liver and Kidneys develop quicker and take up too much space

Question 25

In what week does the gut tube move back into the body cavity?

Answer 25

Week 10. Liver growth slows, abdominal cavity space increases.

Question 26

What is Ompalocele?

Answer 26

Herniation of the abdominal viscera through an enlarged umbilical ring

Question 27

Remnants of a vitelline duct can form?

Answer 27

Meckel's diverticulum