The Respiratory System SEM1 Flashcards
What respiratory sturctures make up the conducting zone
Trachea
Bronchi
Bronchioles
Terminal bronchioles
What respiratory structures make up the transitional and respiratory zones
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
What is the role of goblet cells in the lungs
Produce mucus in the lungs
What are the types of alveolar cells
Type I pneumocyte
Type II pneumocyte
What is the role of the conducting airways
Air conditioning function: warming, filtering and humidifying
What are the mechanisms of inspiration
Diaphgram contraction
Intercostal muscle contraction
What is the underlying mechanism of expiration
Alveolar pressure becomes higher than the atmospheric pressure which drives air out of the alveoli
What is elastic recoil
Rebound of the lungs after having been stretched by inhalation
What are the elastic properties of the tissue of the lungs
Collagen and elastin
What does type II pneuomocyte produce
Produces surfactant
What are the units of pressure (atmospheric pressure)
KPa
What is the transport of oxygen
O2 diffuses into blood at respiratory surface, then transported in the blood, then diffuses into the tissue
What is the normal value that O2 that haemoglobin can carry
1.39ml O2 per g Hb
What is the transport of CO2
CO2 diffuses into the blood from tissues, transported in blood, diffuses across the respiratory surface and liberated into environment
What is a result of deoxygenated blood at the tissues
Able to take up more CO2
What is the result of oxygenation of blood in the lung
Assists unloading of CO2 from blood
What is hypoventilation
Lower than normal volumes of fresh air entering alveoli
What causes an increased resistance in alveolar ventilation
Can be due to:
Accumulation of mucus in upper airways in response to infection/allergy or inflammation of bronchial tubes
What can cause hypoventilation
Decreased lung compliance
Increased resistance
CNS depression
What are pathological changes that adversely affect gas exchange
Decrease in alveolar surface area (amphysema)
Inc. in thickness of alveolar-capillary exchange barrier (fibrotic lung disease)
Inc. in diffusion distance between alveolar space and blood (pulmonary edema)
What is the role of slowly adapting receptors (SARs, stretch receptors)
Prevent over inflation
What is the role of rapidly adapting receptors (RARs, irritant receptors)
Respond to noxious stimuli
What is the role of J receptors
Respond to increased alveolar fluid, pulmonary congestion, inflammatory mediators - all associated with lung disease
Where are central chemoreptors located
In the medulla in the brain stem
