Microscopic Anatomy of the Airways Flashcards
4 key functions of the respiratory system
Inspiration and exhalation of air
Gas exchange
Olfaction
Phonation
What type of epithelium is in the airways
Respiratory epithelium
Pseudostratified ciliated columnar epithelium with goblet cells
3 types of cells in resp epithelium
Ciliated columnar cells
Goblet cells
Basal cells
2 layers of airway lining fluid
Mucus layer
Periciliary layer
Mucus is produced by…
Goblet cells
Seromucus glands
4 layers of trachea
Mucosa
Submucosa
Cartilage
Adventitia (loose CT)
2 changes that happen when the bronchi enter the lungs
Rings of cartilage are replaced by irregular cartilage plates
There is a circular layer of smooth muscle
5 layers of the bronchi
Mucosa Muscularis Submucosa Cartilage Adventitia
3 changes that occur as the intrapulmonary bronchi become smaller
The amount of cartilage decreases
Respiratory epithelium becomes reduced in height
Layer of smooth muscle
2 changes that make bronchi into bronchioles
No cartilage
No submucosal glands
Club cells
Non-ciliated, dome shaped
In smaller bronchioles
Lung protective functions (surfactant, detox, inflammation control, make enzymes to breakdown mucus, and lyzosyme)
Differences between main bronchi and intrapulmonary bronchi
Main: irregular plates of cartilage, smooth muscle, numerous seromucous glands in submucosa
Intrapulmonary: cartilage reduced as airway gets smaller, smooth muscle, seromucous glands only in larger airways, resp epithelium reduced in height as airways get smaller
Epithelium in bronchioles
Simple columnar and simple cuboidal
Club cells replace goblet cells
Respiratory bronchioles
Do both air conduction and gas exchange
Alveoli extend from lumen
Type 1 pneumocytes
Thin squamous cells
Large surface area to facilitate gas exchange
Linked by tight junctions
Cover 95% of alveolar surface