measuring ventilation

Question 1

explain how a spirometer works

Answer 1

• used to measure lung volume
• a person breathes into an airtight chamber which leaves a trace on a graph which shows the volume of the breaths

Question 2

define vital capacity

Answer 2

• the maximum volume of air that can be taken in or expelled from the lungs in one breath
• can be calculated from the spirometer graph by finding the maximum amplitude

Question 3

define tidal volume

Answer 3

• the volume of air we breathe in and out during each breath at rest
• can be calculated from the spirometer graph by finding the amplitude at rest

Question 4

define breathing rate

Answer 4

• the number of breaths we take per minute
• can be calculated from the spirometer graph by counting the number of peaks in one minute