PHYSIOLOGY

• What is the primary function of the respiratory system?

  To facilitate gas exchange for metabolism
• Why do cells require oxygen?

  For energy production through metabolic activities
• What is produced as a waste product of cellular respiration?

  Carbon Dioxide
• What are the main muscle groups involved in breathing?

  Diaphragm and intercostal muscles
• What happens to lung volume during inhalation?

  Lung volume increases
• What is pulmonary ventilation?

  The process of drawing air into the lungs
• What is external respiration?

  Gas exchange between lungs and blood
• What is internal respiration?

  Gas exchange between blood and body cells
• What occurs during inspiration?

  Diaphragm contracts, lowering intrathoracic pressure
• What happens during expiration?

  Diaphragm relaxes, increasing intrathoracic pressure
• What is the role of cilia in the respiratory system?

  To filter out small inhaled particles
• What is the total lung capacity?

  Approximately 5-6000 mls
• What is tidal volume?

  Amount inhaled and exhaled in one cycle
• What percentage of oxygen is bound to haemoglobin?

  98.5%
• How is oxygen transported in the blood?

  Dissolved and bound to haemoglobin
• What is the primary factor affecting lung compliance?

  Elasticity of lung tissue
• What does high compliance indicate?

  Lungs expand easily
• What is airway resistance?

  Resistance within the airways during breathing
• What can increase airway resistance?

  Diseases causing bronchoconstriction or inflammation
• What is the role of chemoreceptors in respiration?

  They respond to chemical changes in blood
• Where are central chemoreceptors located?

  In the Medulla Oblongata
• What stimulates peripheral chemoreceptors?

  Changes in CO2 and low oxygen levels
• What is hypoxic drive?

  Respiration stimulated by low oxygen levels
• What happens during apnoea?

  Breathing temporarily stops
• What could cause apnoea?

  Obstruction or central nervous system issues
• What happens to O2 and CO2 levels during apnoea?

  O2 decreases, CO2 increases
• What are the three stages of breathing?

  1. Pulmonary Ventilation: Drawing air into lungs
  2. External Respiration: Gas exchange in lungs
  3. Internal Respiration: Gas exchange in body cells
• What are the factors affecting breathing?

  • Elasticity: Lung's ability to return to shape
  • Compliance: Ease of lung expansion
  • Airway Resistance: Resistance in airways
• What are the tidal volumes and their definitions?

  • Tidal Volume: Air inhaled/exhaled in one cycle
  • Inspiratory Reserve Volume: Forcibly inhaled air
  • Expiratory Reserve Volume: Forcibly exhaled air
  • Residual Volume: Air left after exhalation
  • Vital Capacity: Total air exhaled after inhalation
• What are the roles of surfactant in the lungs?

  • Increases lung compliance
  • Helps keep alveoli open
  • Prevents atelectasis in neonates
• What are the effects of chronic hypercapnia on chemoreceptors?

  • Decreases sensitivity to CO2
  • Stimulates respiration based on low O2 levels