Respiratory Anatomy Flashcards
(43 cards)
Conducting zone goes down to…
terminal bronchioles
“Anatomic Dead Space”
Conducting zone - warms, humidifies, and filters air but does not participate in gas exchange
Cartilage and goblet cells extend to….
end of bronchi
Pseudostratified ciliated columnar cells extend to
beginning of terminal bronchioles
Cuboidal cells begin at
terminal bronchioles
Airway smooth muscle extend to
end of terminal bronchioles
Respiratory zone consists of:
respiratory bronchioles, alveolar ducts, and alveoli
Participates in gas exchange
Respiratory zone
Cell type in respiratory bronchioles
cuboidal cells
Cell type in alveoli
simple squamous
Clear debris and participate in immune response
Alveolar macrophages
Type I Pneumocytes:
97% of alveolar surface. Squamous, line alveoli, optimal for gas diffusion
Type II Pneumocytes:
Secrete pulmonary surfactant (lecithin)
Cuboidal, clustered.
Serve as precursors to type I cells and other type II cells. Proliferate during lung damage.
Club (Clara) cells
Nonciliated; low-columnar/cuboidal with secretory granules.
Secrete component of surfactant; degrade toxins; act as reserve cells.
Collapsing pressure (P) =
P = 2 (surface tension) / radius
Surfactant (purpose)
Decreases alveolar surface tension and prevents alveolar collapse (atelectasis).
Surfactant (properties)
Complex mix of lecithins, most important of which is dipalmitoylphosphatidylcholine.
Dipalmitoylphosphatidylcholine
Most important lecithin in surfactant
La Place’s Law
Alveoli have increased tendency to collapse on expiration as radius decreases
Fetal surfactant synthesis begins at
26 weeks gestation
Fetal surfactant levels are mature at
35 weeks gestation
Fetal lung maturity is indicated by:
Lecithin-to-sphingomyelin ratio >2.0 in amniotic fluid
Right lung has how many lobes?
3
Left lung has how many lobes?
2
Left has Less Lobes and Lingula (homologue of right middle lobe)
Instead of middle lobe, left lung has space occupied by heart.
