Structure And Function of the Airways Flashcards
What is meant by dichotomous branching?
Where each part of the bronchi splits into two
What does the cartilage around the bronchi provide?
Mechanical stability
What is the main unbranched part of the airway called?
Trachea
What is the first branch of the trachea called?
Primary bronchus
What is the carina?
A ridge at the base of the trachea (windpipe) that separates the openings of the right and left main bronchi (the large air passages that lead from the trachea to the lungs).
What is an alveolar duct?
Ducts that connect the alveolar sacs to the bronchioles
Do the respiratory bronchioles contain cartilage?
no - they are non-cartilaginous
What do Type II Pneumocytes secrete and why?
Surfactant - in order to reduce surface tension
What happens to Type II cells if Type I cells become damaged?
They form type 1 cells
What do the anti-proteases produced by Type 2 pneumocytes do?
They degrade foreign proteases which may have entered into the airways
Which type of alveolar cell is involved in xenobiotic metabolism?
Type 2
Describe the structure of Type 1 alveolar cells?
They are thin, and very flat that form a barrier between alveolus and capillaries
What percentage of the alveolar surface do type 1 cells cover?
95%
What percentage of the alveolar surface do type 2 cells cover?
5%
Are there more type 1 or type 2 alveolar cells?
Type 2
What are the two basic functions of the respiratory airway?
Conducting oxygen to the alveoli and conducting carbon dioxide out the lungs
What are the three things which facilitate the efficient gas exchange?
- Mechanical stability from cartilage
- Control of calibre from smooth muscle
- Protection and cleaning to remove foreign particles
What are the three regions of the pharynx?
Nasopharynx, oropharynx and laryngopharnx
What is the pharynx?
A common passageway for food, liquids and air
What do the conchae found in the nose do?
They contribute to the warming and humidification of intra-nasally-inhaled air
Why must the air be warmed before being breathed in?
Cool air damages the alveoli
What property of the conchae makes them able to humidify nasally inhaled air?
They are highly vascular
What filters out large particles from nasally inhaled air?
Nasal hairs
What is the main function of the goblet cells?
To produce mucus
What are the 7 types of airway cell types?
Lining cells Contractile Secretory Neuroendocrine Connective tissue Vascular Immune