Exchange Surfaces

Question 1

Tidal Volume

Answer 1

Volume of air that moves in OR out each resting breath, usually around 500cm³

Question 2

Vital Capacity

Answer 2

The volume of air that can be breathed in when the strongest possible exhalation is followed by the deepest breath in (eg, force out as much air as possible. This is the start point, then breathe in as deep as possible = the vital capacity)

Question 3

Inspiratory reserve volume

Answer 3

Maximum volume breathed in over and above normal tidal

Question 4

Expiratory reserve volume

Answer 4

The extra air that can be forced out of the lungs over and above normal volume breathed out

Question 5

Residual volume

Answer 5

Volume of air left in the lungs when you have exhaled as hard as possible. Cannot be directly measured

Question 6

Breathing rate

Answer 6

Number of breaths per minute

Question 7

Ventilation rate

Answer 7

Tidal volume * breathing rate (min⁻¹)

Question 8

Oxygen uptake

Answer 8

The volume of oxygen absorbed by the blood. It is assumed that this is equal to the volume of carbon dioxide absorbed by the soda lime