Resp development

Question 1

Time of formation of laryngotracheal diverticulum

Answer 1

4th week

Question 2

Stages of formation of laryngotracheal diverticulum

Answer 2

1. Ventral outgrowth of rostral foregut
2. lateral edges pinch in > tracheoesophageal septum
3. septum divides into esoph dorsally and blind tube ventrally
4. Endoderm forms lining
5. splanchnic mesoderm forms connective tissues, muscles pleura

Question 3

if septum doesn’t close properly

Answer 3

tracheo-esophageal fistula

Question 4

freq of trach-eso fistula

Answer 4

1:3000

Question 5

tissue that controls branching of bronchi

Answer 5

mesoderm via FGF-10

Question 6

Timelines of lung dev

Answer 6

7 weeks - segmental bronchi
24 weeks - 17 divs> resp. bronchioles
26-28 weeks - enough alveoli to survive
branching continues to 8th year

Question 7

Producer of sufactant

Answer 7

alveoli

Question 8

function of surfactant

Answer 8

reduce surface tension and increase lung compliance

Question 9

4 ways to prevent resp. distress

Answer 9

1. delay delivery
2. predict pulmonary immaturity
3. speed maturation
4. deliver surfactant

Question 10

Growth of lung depends of 4 factors

Answer 10

1. space in throax
2. fetal lung fluid
3. amniotic fluid - GFs
4. practice breathing

Question 11

Source of diaphragm

Answer 11

cranial part of septum transversum

Question 12

Which pleuorperitonal canal closes first

Answer 12

R side – will have diaphragmatic hernia on left side