development of lungs

Question 1

the laryngotracheal groove evaginates to form…

Answer 1

laryngotracheal diverticulum

Question 2

what does the laryngotracheal diverticulum elongate and push into?

Answer 2

splanchnic mesoderm

Question 3

distal portion of laryngotracheal diverticulum…

Answer 3

swells to become respiratory bud

Question 4

respiratory bud elongates and…

Answer 4

divides into right and left bulbs called primary bronchial buds

Question 5

right main bronchus

Answer 5

more vertical and larger

Question 6

proximal diverticulum will form

Answer 6

trachea and larynx

Question 7

lung maturation during weeks 5-28

Answer 7

primary bronchial buds split to form secondary bronchial buds, then split to become tertiary bronchial buds
division continues to form the bronchial tree

Question 8

secondary bronchial bud becomes

Answer 8

lobar bronchi

Question 9

tertiary bronchial bud becomes

Answer 9

segmental bronchi

Question 10

visceral pleura comes from

Answer 10

splanchnic mesoderm

Question 11

parietal pleura comes from

Answer 11

somatic mesoderm

Question 12

fusion of the tracheoesophageal folds in the lateral wall forms

Answer 12

tracheoesophageal septum

Question 13

the tracheoesophageal septum divides a portion of the foregut which way

Answer 13

ventrally and laterally

Question 14

the ventral portion of the tracheoesophageal septum becomes

Answer 14

the trachea and the larynx

Question 15

the dorsal portion of the tracheoesophageal septum becomes

Answer 15

the esophagus

Question 16

what occurs if the tracheoesophageal folds fail to properly

Answer 16

formation of tracheoesophageal fistula (TEF)

Question 17

tracheoesophageal fistula

Answer 17

abnormal connection between trachea and esophagus

Question 18

complications of a tracheoesophageal fistula

Answer 18

coughing, choking, gastric reflux, pneumonia

Question 19

what is needed for normal lung development?

Answer 19

adequate space in thoracic cavity and adequate volume of amniotic fluid

Question 20

why do fetal breathing movements occur?

Answer 20

to practice breathing movement and to move amniotic fluid in order to nourish developing tissues

Question 21

4 stages of lung maturation

Answer 21

pseudoglandular, canalicular, saccular, and alveolar

Question 22

pseudoglandular time frame

Answer 22

weeks 5-17

Question 23

what is formed during the pseudoglandular stage

Answer 23

terminal bronchioles and connective tissue

Question 24

what is the only thing not formed during the pseudoglandular stage?

Answer 24

structures for gas exchange

Question 25

canalicular time frame

Answer 25

weeks 16-25

Question 26

what happens during the canalicular stage?

Answer 26

bronchi and terminal bronchiole lumen become larger, high vascularization of lung tissue

Question 27

what is formed during the canalicular stage?

Answer 27

respiratory bronchioles, primordial alveolar ducts, and terminal sacs

Question 28

saccular time frame

Answer 28

24 weeks to birth

Question 29

what is formed during the saccular stage?

Answer 29

blood-air barrier, type I pneumocytes, and type II pneumocytes

Question 30

type I pneumocytes

Answer 30

site of gas exchange

Question 31

type II pneumocytes

Answer 31

secrete pulmonary surfactant

Question 32

alveolar time frame

Answer 32

32 weeks to 8 years

Question 33

what happens during the alveolar stage?

Answer 33

epithelium thins, capillaries bulge into alveolar sacs
alveoli mature and increase in number

Question 34

respiratory distress syndrome

Answer 34

rapid, labored breathing after birth because lungs are under inflated and alveoli contain fluid

Question 35

endoderm lining gives rise to

Answer 35

pulmonary epithelium, glands of larynx, trachea, bronchi, mucosal lining and epithelial cells of the alveoli

Question 36

splanchnic mesoderm gives rise to

Answer 36

connective tissue, cartilage, visceral pleura, and smooth muscle

Question 37

splanchnopleuric mesoderm gives rise to

Answer 37

muscle and cartilage of bronchi