Gas exchange - measuring lung volumes Flashcards
What apparatus is used to investigate the effect of exercise on ventilation?
Spirometer
A spirometer measures lung volumes and ventilation.
What is the main component of a spirometer that allows it to measure breathing?
A chamber filled with water covered by a hinged plastic lid
The lid moves with breathing, allowing measurement of lung volumes.
How does a spirometer measure lung capacity?
By filling the chamber with air
It determines lung capacity in different conditions.
What does a spirometer measure when filled with oxygen and soda lime?
Oxygen consumption
Soda lime absorbs carbon dioxide during the measurement.
What are the two methods used to create spirometer traces?
- Drawing a line on a revolving drum
- A computer drawing a graph of the results
These methods visualize the breathing patterns.
List three measurements that can be made using spirometer traces.
- Ventilation rate
- Tidal volume
- Vital capacity
These measurements help assess lung function.
What is tidal volume?
The volume of air inhaled and exhaled during normal breathing
Tidal volume increases during exercise.
What happens to tidal volume during exercise?
It increases
More air is moved in and out of the lungs.
What is the maximum volume of air that can enter the lungs during inspiration called?
Maximum inspiratory level
This is a key measure of lung capacity.
What is the maximum volume of air that can be exhaled during expiration called?
Maximum expiratory level
This indicates the lung’s exhalation capacity.
Define inspiratory reserve volume.
The difference between the maximum inspiratory level and tidal volume
It indicates extra air that can be inhaled.
Define expiratory reserve volume.
The difference between the maximum expiratory level and tidal volume
It indicates extra air that can be exhaled.
What does vital capacity (VC) refer to?
The total amount of air exhaled after taking a deep breath
VC is important for assessing lung function.
How is vital capacity calculated?
VC = TV + IRV + ERV
TV = Tidal Volume, IRV = Inspiratory Reserve Volume, ERV = Expiratory Reserve Volume.
How is ventilation rate determined?
By counting the number of inhalations or exhalations per minute
This reflects the breathing frequency.
True or False: Exercise causes a decrease in ventilation rate.
False
Exercise increases the ventilation rate.
