B3.1 - ventilation (6f) Flashcards
What is ventilation?
Movement of fluid (air or water) to support the exchange of gases between lungs and air, or gills and water.
What are the components of the respiratory system?
- Alveoli
- Bronchiole
- Bronchus
- Trachea
- Intercostal muscles (internal and external)
- Ribs
- Diaphragm
What is the process of inspiration?
- Diaphragm contracts.
- Diaphragm flattens and moves downwards. - External intercostal muscles contract.
- Ribs move upwards and outwards. - Volume of thorax increases.
- Pressure in thorax decreases (below atmospheric pressure).
- Air flows into the lungs.
What occurs during the process of passive expiration?
- Diaphragm muscles relax.
- Diaphragm moves upward and becomes domed. - External intercostal muscles relax.
- Ribs move downwards and inwards. - Volume of thorax decreases.
- Pressure in thorax increases (above atmospheric pressure).
- Air flows into lungs.
How is forced expiration different to passive expiration?
- Abdominal muscles contract, forcing the diaphragm up.
- Internal intercostal muscles contract, ribs pulled down hard.
What is a spirometer?
Apparatus that uses data logging to measure changes in air volume in a person’s lungs over a given period of time.
What is tidal volume?
The volume of air moving into and out of the lungs at rest.
What is vital capacity?
The maximum volume of air that can be inhaled or exhaled in one breath.
What is inspiratory reserve volume?
The maximum volume that can be inhaled beyond normal inhalation.
What is expiratory reserve volume?
The maximum volume that can be exhaled beyond normal exhalation.
How do we calculate the total volume of air inhaled during one minute?
Tidal volume x Ventilation rate
How could we calculate mean tidal volume after exercise?
1) Measure volume differences between peak and trough.
2) Repeat for several breaths and determine mean.
