Prenatal Lung Development

Question 1

human lung epithelium is derived from which primary layer of an early embryo

Answer 1

endoderm

Question 2

surrounding mesenchyme (provide support and structure to lung tissue) is derived from which primary layer of an early embryo

Answer 2

mesoderm

Question 3

human lung development occurs through how many morphological stages

Answer 3

5

Question 4

why do the 5 morphological stages of human lung development overlap in timing

Answer 4

because different stages happen in different lung regions at the same time

Question 5

list the 5 morphological stages of human lung development

Answer 5

• embryonic
• pseudoglandular
• canalicular
• saccular
• alveolar -

Question 6

[5 stages of lung development] embryonic occurs in which weeks post conception

Answer 6

4-7 weeks pcw

Question 7

[5 stages of lung development] psuedoglandular occurs in which weeks post conception

Answer 7

5-17 pcw

Question 8

[5 stages of lung development] canalicular occurs in which weeks post conception

Answer 8

16-26 pcw

Question 9

[5 stages of lung development] saccular occurs in which weeks post conception

Answer 9

26-36 pcw

Question 10

[5 stages of lung development] alveolar occurs in which weeks post conception

Answer 10

36 pcw - 3 years post birth

Question 11

[embryonic] the primary left and right lung buds appear from where towards the end of week _ after conception

Answer 11

• foregut endoderm
• week 4

Question 12

[embryonic] the primary left and right lung buds ____ ________ to set up the overall lobular structure of the lung by end of week _

Answer 12

• branch rapidly
• week 5

Question 13

[pseudoglandular] the lung continues to grow by

Answer 13

branching morphogenesis

Question 14

[pseudoglandular] what is laid down and begins to differentiate with cartilage

Answer 14

the airway tree

Question 15

[pseudoglandular] what muscle and what glands develop

Answer 15

• smooth muscle
• mucous glands

Question 16

[pseudoglandular] foetal breathing movements begin by what weeks

Answer 16

10-11 weeks after conception

Question 17

[pseudoglandular] accumulation of lung liquid in foetal lungs is critical for what

Answer 17

lung growth

Question 18

[pseudoglandular] blood vessel development occurs concurrently with what

Answer 18

epithelial branching

Question 19

[pseudoglandular] airway epithelium begins to what

Answer 19

differentiate

Question 20

[canalicular] what happens to existing airways

Answer 20

grow in size

Question 21

the last stage of branching morphogenesis occurs during which development stage

Answer 21

canalicular

Question 22

[canalicular] describe the last stage of branching morphogenesis

Answer 22

3 more rounds of epithelial branching occur to produce future alveoli

Question 23

[pseudoglandular] describe the vessels location

Answer 23

run alongside airways but branch more slowly

Question 24

[canalicular] the future alveoli develop from what

Answer 24

the most distal epithelial tubes

Question 25

[canalicular] what happens to the most distal epithalial tubes

Answer 25

- widen into airspaces - surrounding mesenchyme thins

Question 26

[canalicular] during this stage of development, close proximity develops between what

Answer 26

capillary networks & regions of the distal epithelial tubes that will form airspaces

Question 27

[saccular] is marked by the differentiation of what

Answer 27

alveolar epithelial cells

Question 28

[saccular] what begins due to the differentiation of alveolar epithelial cells

Answer 28

production and secretion of surfactant by type II alveolar cells

Question 29

[saccular] what happens to the distal airspaces

Answer 29

become thin-walled terminal saccules[s

Question 30

[saccular] what is the location of the terminal saccules

Answer 30

cluster at the ends of the airways

Question 31

[saccular] what happens to the terminal saccules

Answer 31

- increase further in size - become completely wrapped in a capillary bilayer

Question 32

[alveolar] alveoli form within each ____

Answer 32

airway sac

Question 33

[alveolar] how are distal saccules subdivided into alveoli

Answer 33

growth of septae from saccular walls