Introduction to Respiration

Question 1

3 tubular systems

Answer 1

airway, pulmonary blood supply and bronchial blood supply

Question 2

5 stages of lung development:

lead to formation of the alveolar blood gas barrier

Answer 2

1) Embryonic
2) Pseudoglandular
3) Canalicular
4) Saccular
5) Alveolar

Question 3

embryonic stage

Answer 3

establishes basic lung structure (lobes) as a template for further growth
(26 days to 6 weeks)

Question 4

pseudoglandular stage

Answer 4

establishes the branches of the network of gas conducting airway

Question 5

canalicular stage

Answer 5

formation of the blood-gas (alviolar- capillary) barrier

Question 6

saccular stage

Answer 6

formation of the respiratory acinus-the zone of gas exchange

Question 7

alveolar stage of lung development

Answer 7

formation of the alveolus and high surface area for gas exchange. 5X increase in surface area for 2X increase in lung volume.

Question 8

irregular dichotomous branching

Answer 8

achieves even dispersal of gas among terminal airway branches. mechanical strain dispersed evenly among units.

regulated increase in the number of airways at each branch dispreses airflow resistance which would otherwise increase with distance into the lung