2. Mechanics of breathing Flashcards
What is tidal volume - TV ?
Volume of air breathed in and out of lung at each breath
What is expiratory reserve volume- ERV ?
Maximum volume of air expelled from lungs at end of normal expiration
What is inspiratory reserve volume- IRV ?
Maximum volume of air drawn into the lungs at end of normal inspiration
What is residual volume- RV ?
Volume of gas in the lungs at the end of maximal expirationCannot voluntarily expire it Stops alveoli collapsing Reduces work of breathing Provides volume of air that can allow gas exchange to take place between breaths
What is vital capacity- VC ?
Total amount of air we expire TV + ERV + IRV
What is functional residual capacity- FRC ?
Volume of air that is in our lungs at the end of normal expirationERV + RV
What is total lung capacity- TLC ?
Volume of air in lungs after maximum inspiration VC + IRV
What is inspiratory capacity- IC ?
Volume breathed in from quiet expiration to maximum inspirationTV + IRV
What is forced vital capacity- FVC ?
The maximal volume of air that a subject can expel in one maximal expiration from a point of maximal inspiration
What is FEV1 -forced expiratory volume in one second ?
The maximal volume of air that a subject can expel in one second from a point of maximal inspiration
What is FEV1:FVC ?
Fraction of forced vital capacity expired in 1 second
What is Boyle’s law ?
states that the pressure exerted by a gas is inversely proportional to its volume (P a 1/V)gases move from areas of high pressure to areas of low pressure
What is Dalton’s law ?
States the total pressure of a gas is the sum of the pressures of the individual gases
What is Charles law ?
States the volume occupied by a gas is directly related to the absolute temperature
What is Henry’s law ?
states that the amount of gas dissolved in a liquid is determined by the pressures of the gas and its solubility in a liquid
How does the mechanics of breathing occur ?
Because the thoracic cavity changes volume
Based on Boyle’s law when volume increases what happens to pressure ?
When volume increases = pressure decreases