Respiratory System Flashcards
Spirometry
Total lung volume
Spirometry
Tidal volume
Spirometry
Functional residual capacity
Spirometry
Residual volume
Spirometry
Inspiratory and expiratory reserve volume
Spirometry
Vital capacity
Graph of Spirometry
Total lung volume
Sum of all volumes in the lungs.
Note that this can not be measured by spirometry (only lung capacity can be measured).
Tidal volume
Volume of a normal breath.
Functional residual capacity
Volume left in lungs after a natural exhalation.
Residual volume
Volume left in lungs after a full forced exhalation. In order to keep alveoli open, the lung cannot fully deflate, resulting in residual volume
Inspiratory and expiratory reserve volume
Additional volume that can be inhaled after a natural breath in, or exhaled after a natural breath out.
Vital capacity
Volume of a full forced inhalation and exhalation. Equals the total lung capacity minus the residual volume.
Nostrils of nose, which contain nose hairs called vibrissae that help protect from pathogens.
Nares
Connects the mouth to the esophagus.
Allows passage of both air and food.
Pharynx
Connects the mouth to the trachea.
Allows air, but food is blocked by the epiglottis.
Larynx
Central airway. Branches into two bronchi.
Trachea
Branch of the airway which enters into each lung. Branches further into bronchioles.
Bronchi
The lining around the lungs. Allows movement with minimal friction.
Pleura
Bicarbonate buffer equation
CO2 + H2O ⇌ H2CO3 ⇌ H+ + HCO3-
Application of Le Chatelier’s principle to blood gas physiology
To regulate blood pH, the body will change respiration rate which affects the blood CO2 concentration.
This shifts the equilibrium of the bicarbonate buffer system to modulate H+ concentration.
If the blood pH is too low, the body will compensate by increasing respiration rate to blow off more CO2.
Blood acidosis
If the blood pH is too high, the body will compensate by decreasing respiration rate to blow off less CO2.
Blood alkalosis
Breathing mechanisms
Differential pressure
Intrapulmonary pressure vs Intrapleural pressure
Intrapulmonary pressure: same as atmospheric pressure because lung is open to outside.
Intrapleural pressure: lower than atmospheric pressure to keep lung from collapsing.
Occurs through negative pressure mechanism.
The diaphragm muscle pulls downward, decreasing intrapleural pressure and causing lung expansion.
Inhalation
Usually a passive process due to muscle relaxation.
Active exhalation recruits the intercostal muscles to help force air out.
Exhalation
Alveoli are coated with surfactant which helps decrease surface tension, preventing collapse.
Surface tension
Respiratory control center of brain is the
Respiratory control center of brain is the medulla oblongata.
When blood pH is acidic, respiration increases to blow off CO2 and increase bicarbonate buffer.
Amount of CO2 produced per O2 consumed.
Respiratory quotient
