Respiratory Histology Flashcards
What is the function of the nasal cavity the respiratory system?
Warming, moistening and filtering of the inspired air
What type of epithelium does the roof of the nasal cavity contain?
Olfactory epithelium
What is the function of olfactory epithelium?
Smelling
Where is the olfactory epithelium in the nasal cavity located?
Under the cribriform plate of the ethnic bone
What type of epithelium lines the initial part of the nasal cavity?
Keratinised stratified squamous epithelium
What type of epithelium lines the deeper part of the nasal cavity?
Pseudo stratified ciliated columnar epithelium with goblet cells aka Respiratory epithelium
What is the function of secretory glands in respiratory epithelium?
Production of mucin
What is the function of basal lamina in respiratory epithelium?
Reproduce epithelium (replaced every few weeks)
What is found underneath the respiratory epithelium?
The lamina propria
What is the lamina propria?
Band of connective tissue containing seromucous glands (M & S) and a rich venous plexus
What type of epithelium lines the oropharynx and epiglottis?
Non-keratinised stratified squamous epithelium
Which part of the larynx is not covered in respiratory epithelium?
The vocal folds and adjacent structures
What type of epithelium lines the vocal folds and adjacent structures?
Stratified squamous epithelium
What type of epithelium lines the trachea?
Respiratory epithelium
What backs the resp. epithelium of the trachea?
Basal lamina
Lamina propria of connective tissue with abundant elastic fibres and submucosa of loose connective tissue that includes many seromucous glands
The trachea is maintained and held open by _____
hyaline cartilage
What lines the bronchi?
Respiratory epithelium
What is the lamina propria in the bronchi made of?
Discontinuous layer of smooth muscle and seromucous glands
How do the cells of the wall of the conducting airways obtain oxygen, nutrients, etc.?
Perfused by the bronchial arteries (branch off the aorta)
How does the epithelium of the bronchioles change superiorly to inferiorly?
Decrease in height from columnar to cuboidal
What is the lamina propria made of in the bronchioles?
Smooth muscle + elastic and collagenous fibres
What are the terminal portions of the respiratory tree?
Alveoli
What does the alveolar epithelium consist of?
Type I & II alveolar cells
What is the function of type I alveolar cells?
Provide a minimal barrier permeable to gases for gas exchange
What shape do type II alveolar cells have?
Polygonal shape
Which part of type II alveolar cells secrete surfactant?
Lamellar bodies
What is the function of alveolar surfactant?
Reduce surface tension of the air-fluid interface of alveoli to reduce the tendency of alveoli to collapse after expiration
What is the purpose of alveolar macrophages?
Remove inhaled particles that weren’t removed by the mucociliary escalator
What is the function of the goblet cells of the epithelium together with the submucosal glands in the trachea?
Produce a viscous fluid that casts the surface of the airway, trapping particles that are then propelled out of the airway by cilia
