Wed Arlen Respiratory development

Question 1

connective tissue, cartilage, and smooth muscle for the bronchial tubes developes from the ___ of the forgut, except for laryngeal cartilage, which develops from the ___

Answer 1

splanchnic mesoderm

neural crest mesenchyme

Question 2

laryngeal muscles are innervated by what nerves (also which do sensory and motor)

Answer 2

vagus nerve (superior laryngeal (sensory above vocal chords) and recurrent laryngeal (motor to vocal chord and sensory below))

Question 3

what are the laryngeal muscles developed from?

Answer 3

the myoblasts of the fourth and sixth pairs of pharyngeal arches

Question 4

tracheoesophageal fistula

most common type?

why does it happen?

Answer 4

esophagus connects to the trachea

most common type is esophageal atresia, where the esophagus just stops early, goes back into the trachea and continues down off the trachea further down.

happens due to abnormal partitioning of the laryngotracheal tube near the tracheoesophageal septum

Question 5

type I and type II alveolar cells

Answer 5

type I pneumocytes - cells that line the alveolus and participate in gas exchange

type II - secrete pulmonary surfactant (phospholipid and protein)

Question 6

hyaline membrane disease

AKA

respiratory distress syndrome

Answer 6

caused by a deficiency of surfactant and injury to the alveolar wall resulting in protein-rich, fibrin-rich exudation into the alveolar spaces

Persistently low O2
tension can lead to risk of PDA