respiratory physiology Flashcards
(12 cards)
What are the main functions of the respiratory system?
Exchange of oxygen and carbon dioxide, regulation of blood pH, and participation in vocalization and immune defense.
What are the components and organization of the respiratory system?
It includes the conducting zone (trachea, bronchi, bronchioles) and the respiratory zone (alveoli, respiratory bronchioles).
What is the role of type II pneumocytes?
They produce pulmonary surfactant, reduce alveolar surface tension, and have regenerative capacity.
What are lung volumes and capacities?
They are measurements of air in the lungs at different stages of the respiratory cycle, including tidal volume, inspiratory reserve, etc.
What is spirometry used for?
To measure lung function, diagnose obstructive/restrictive diseases, and monitor treatment effects.
What is the difference between inspiration and expiration?
Inspiration is active and increases thoracic volume; expiration is typically passive and decreases thoracic volume.
What is pulmonary compliance and elastance?
Compliance is lung stretchability; elastance is the ability to recoil after stretch.
How does the autonomic nervous system regulate airway resistance?
Sympathetic stimulation dilates airways (β2 receptors); parasympathetic constricts (muscarinic receptors).
How does gas exchange occur in the lungs?
By diffusion across the respiratory membrane, driven by partial pressure gradients of O₂ and CO₂.
How is oxygen transported in the blood?
1.5-2% dissolved in plasma; 98% bound to hemoglobin in red blood cells.
How is carbon dioxide transported in the blood?
5-7% dissolved in plasma, ~3% as carbaminohemoglobin, and >85% as bicarbonate in red blood cells.
How is breathing controlled?
Via brainstem centers (medulla and pons), chemoreceptors for O₂/CO₂, mechanoreceptors, and voluntary inputs from the cortex.
