Embryology 3

Question 1

Where does the primitive oesophagus bud from?

Answer 1

foregut - laryngeotracheal groove

Question 2

At what week does the primitive oesophagus bud?

Answer 2

week 4

Question 3

Are the larynx and trachea anterior or posterior to the pharynx and oesophagus?

Answer 3

anterior

Question 4

How does the trachea and lung buds form?

Answer 4

Diverticulum (endoderm) covered in mesoderm enlarges

Question 5

What is the name of the septum which develops between the trachea and the oesophagus?

Answer 5

oesophagotracheal septum

Question 6

What mesoderm does the visceral pleura form from?

Answer 6

splanchnic

Question 7

What mesoderm does the parietal pleura form from?

Answer 7

somatic

Question 8

What is a fistula?

Answer 8

An abnormal or surgically made passage involving hollow or tubular organs and sometimes the body surface

Question 9

What is atresia?

Answer 9

Orifice or passage is closed or absent

Question 10

Name the 3 periods in the differentiation of lung buds

Answer 10

embryonic
foetal
postnatal

Question 11

When do the lung buds appear?

Answer 11

day 26 in the form of a respiratory diverticulum

Question 12

How many components go on to make the diaphragm?

Answer 12

4

Question 13

What does the central tendon form from?

Answer 13

septum transversum

Question 14

What does the muscular part of the diaphragm arise from?

Answer 14

Pleuroparietal membrane

peripheral body wall muscle

Question 15

What does the mesentery of the diaphragm go on to form?

Answer 15

Crura of diaphragm

Question 16

What does the gut tube form from?

Answer 16

endoderm

Question 17

When does the folding of the embryo occur?

Answer 17

week 3

Question 18

What does the respiratory diverticulum create?

Answer 18

median trachea and two lateral pockets

Question 19

Where does the respiratory diverticulum form?

Answer 19

ventral part of the digestive tract

Question 20

Where do the pulmonary arteries individuate at?

Answer 20

6 aortic arch

Question 21

What 3 stages make up the foetal period?

Answer 21

pseudoglandular
canalicular
saccular

Question 22

What stage are the pneumocytes formed?

Answer 22

canalicular

Question 23

What percentage of alveoli are formed postnatally?

Answer 23

95%

Question 24

What is respiratory distress syndrome

Answer 24

A disease affecting around 2% of newborns where there is a deficiency in surfactant

Question 25

Name some other congenital conditions of the lung

Answer 25

accessory lobe
lobe of azygos vein
agenesis of lung

Question 26

What is agenesis of the lung?

Answer 26

Failure of primitive lung bud

Question 27

Where us the septum transversum initially located?

Answer 27

opposite C3-C5 somites in week 3

Question 28

Name the 3 major defects of the diaphragm

Answer 28

Does not completely close
hernia
pulmonary hypoplasia

Question 29

What is a hernia?

Answer 29

Bulge or protrusion of an organ through the structure or muscle that contains it

Question 30

What is a hiatal hernia?

Answer 30

When part of the stomach protrudes up through the diaphragm