Simulation · Biology · Class 11
Reading a spirometer trace
From the lesson Respiratory volumes and capacities in Breathing and Exchange of Gases. Change the values and watch what happens.
Reading a spirometer traceBiology · Class 11
The idea behind it
NCERT §14.2.1
- Tidal Volume (TV): the air breathed in or out in one normal breath, about 500 mL. A healthy person therefore moves roughly 6000–8000 mL of air per minute.
- Inspiratory Reserve Volume (IRV): the extra air that can be forcibly inhaled after a normal inspiration, on average 2500–3000 mL.
- Expiratory Reserve Volume (ERV): the extra air that can be forcibly exhaled after a normal expiration, on average 1000–1100 mL.
- Residual Volume (RV): the air the lungs still hold even after a forcible expiration, on average 1100–1200 mL.
- Inspiratory Capacity (IC) = TV + IRV: total air that can be inhaled after a normal expiration.
- Expiratory Capacity (EC) = TV + ERV: total air that can be exhaled after a normal inspiration.
- Functional Residual Capacity (FRC) = ERV + RV: air left in the lungs after a normal expiration.
- Vital Capacity (VC) = ERV + TV + IRV: the greatest volume of air that can be breathed in following a forced expiration, or breathed out following a forced inspiration.
- Total Lung Capacity (TLC) = VC + RV (equivalently RV + ERV + TV + IRV): all the air the lungs can hold at the end of a forced inspiration.