Respriatory System (chp 7) Flashcards
(30 cards)
What are the main structures of the upper respiratory tract?
Nose, nasal cavity, pharynx, larynx.
What are the functions of the upper respiratory tract?
Filter, warm, and humidify air; trap particles with mucus and cilia.
What are the main structures of the lower respiratory tract?
Trachea, bronchi, bronchioles, lungs, alveoli.
What are the functions of the lower respiratory tract?
Air conduction and gas exchange.
What is the function of alveoli?
Gas exchange: oxygen diffuses into blood, CO₂ diffuses out.
What features make alveoli efficient at gas exchange?
Thin walls, large surface area, rich capillary network, moist lining.
What happens during inhalation?
Diaphragm contracts, thoracic volume increases, pressure decreases, air flows in.
What happens during exhalation?
Diaphragm relaxes, thoracic volume decreases, pressure increases, air flows out.
What part of the brain regulates breathing?
Medulla oblongata.
What primarily stimulates breathing rate?
CO₂ levels in the blood.
What is tidal volume?
Normal breath (~500 mL).
What is inspiratory reserve volume?
Extra air you can INHALE after normal inhalation.
What is expiratory reserve volume?
Extra air you can EXHALE after normal exhalation.
What is residual volume?
Air left in lungs after forceful exhalation.
What is vital capacity?
Total volume you can exhale after full inhalation.
What is total lung capacity?
All volumes combined.
What does a spirometer measure?
Lung volumes and capacities.
What can abnormal spirometry indicate?
Obstructive or restrictive lung disease.
How is oxygen transported in blood?
Mostly bound to hemoglobin (Hb); a small amount dissolved in plasma.
How is carbon dioxide transported in blood?
70% as bicarbonate (HCO₃⁻), 20% bound to Hb, 10% dissolved in plasma.
How does the blood maintain a constant pH?
Buffered by the bicarbonate buffer system (HCO₃⁻/H₂CO₃).
What are the causes and symptoms of Asthma?
Bronchiole constriction; wheezing, shortness of breath.
What causes Pneumonia?
Infection filling alveoli with fluid.
What causes Bronchitis?
Infection or irritants (e.g., smoking); excess mucus and coughing.
