Respiratory System

1. What is the main site of gas exchange?

Alveoli


2. What are bronchioles?

Small airways with smooth muscle → can bronchoconstrict or bronchodilate.


3. What is the function of bronchi?

Carry air from trachea → bronchioles.


4. What muscle drives quiet breathing?

Diaphragm


5. What prevents food from entering the trachea?

Epiglottis


6. What is the glottis?

Opening between vocal cords (controls sound).


7. What is the larynx responsible for?

Air passage + voice production.


8. Main function of nasal cavity?

Filter, warm, humidify air.


9. Function of the pharynx (respiratory role)?

Moves air from nasal cavity → larynx.


10. What do the pleura do?

Double membrane that decreases friction and keeps lungs expanded.


11. What does the trachea do?

Carries air to bronchi; has cartilage rings to prevent collapse.


12. Define ventilation.

Movement of air: inspiration + expiration.


13. Upper respiratory system includes?

Nose, nasal cavity, sinuses, pharynx, top half of larynx.


14. Lower respiratory system includes?

Larynx (below vocal cords), trachea, bronchi, bronchioles, lungs, alveoli.


15. What creates turbulent airflow in nose?

Nasal conchae


16. Three regions of the pharynx?

Nasopharynx, oropharynx, laryngopharynx.


17. Largest cartilage of larynx?

Thyroid cartilage (Adam’s apple)


18. Cartilage below thyroid cartilage?

Cricoid cartilage


19. True vs false vocal cords?

True = sound
False = no sound, protective


20. Which lung has 3 lobes?

Right lung


21. Which lung has 2 lobes and cardiac notch?

Left lung


22. Visceral vs parietal pleura?

Visceral = on lung
Parietal = lines thoracic cavity


23. What law explains breathing mechanics?

Boyle’s Law (P ∝ 1/V)


24. What happens during inhalation?

Diaphragm contracts ↓
Thoracic volume ↑
Pressure ↓
Air flows in


25. What happens during exhalation?

Diaphragm relaxes
Volume ↓
Pressure ↑
Air flows out


26. Example of active vs passive phase?

Inhalation = active
Resting exhalation = passive


27. Accessory inhalation muscles?

SCM, external intercostals, pec minor


28. Accessory exhalation muscles?

Internal intercostals, abdominals


29. Define partial pressure.

Pressure made by one gas in a mixture (PO₂, PCO₂).


30. Which direction does oxygen diffuse?

High PO₂ (alveoli) → low PO₂ (blood → tissues)


31. Which direction does CO₂ diffuse?

High PCO₂ (tissues) → low PCO₂ (blood → alveoli)


32. Blood vessels carrying deoxygenated blood to lungs?

Pulmonary arteries


33. Blood vessels returning oxygenated blood to heart?

Pulmonary veins


34. Brain regions controlling breathing?

Medulla oblongata & pons


35. Nerve that controls the diaphragm?

Phrenic nerve


36. What creates surface tension in alveoli?

Water/mucous from Type I alveolar cells


37. What reduces surface tension?

Surfactant from Type II alveolar cells


38. Main cause of respiratory distress in premature infants?

Low surfactant → alveolar collapse


39. Three ways CO₂ is transported?

  1. Dissolved in plasma (7%)

  2. Carbaminohemoglobin (23%)

  3. Bicarbonate ion HCO₃⁻ (70%)


40. What enzyme forms carbonic acid?

Carbonic anhydrase


41. Relation between CO₂ and pH?

↑ CO₂ → ↑ H⁺ → low pH (acidosis)
↓ CO₂ → ↓ H⁺ → high pH (alkalosis)


42. Respiratory acidosis cause?

Hypoventilation / CO₂ retention


43. Respiratory alkalosis cause?

Hyperventilation / CO₂ loss


44. What happens in asthma?

Bronchoconstriction + inflammation + mucous


45. Influenza affects what?

Upper and/or lower respiratory tract


46. Pneumonia mechanism?

Fluid in alveoli → impaired gas exchange


47. Tuberculosis cause + symptoms?

Mycobacterium tuberculosis → cough blood, fever, weight loss


48. COPD includes which 2 diseases?

Chronic bronchitis + emphysema


49. Chronic bronchitis?

Inflammation of bronchi + mucous


50. Emphysema?

Alveoli destroyed → ↓ gas exchange


51. What does spirometry measure?

Air volumes (TV, IRV, ERV, RV)


52. Tidal volume (TV)?

Resting breathing air in/out


53. Residual volume (RV)?

Air left after MAX exhale


54. Inspiratory reserve (IRV)?

Max additional inhale


55. Expiratory reserve (ERV)?

Max additional exhale


56. Vital capacity?

TV + IRV + ERV


57. Total lung capacity?

Vital capacity + RV