A scientist wanted to observe the effects of altitude on the respiratory system of mammals.
Four different species of mammals were placed
in a chamber that underwent gradual changes in
pressure (measured in atmospheres, or atm) lo
simulate the atmosphere at high altitudes. After
5 minutes at each atmospheric pressure tested,
the number of breaths per minute (respiratory
rate) was determined for each fo the 4 mammals
while they remained at rest. The data from the
experiment are shown in the following graph.
(Note: Larger animals typically have slower
respiratory rates. Higher respiratory rates
indicate rapid breathing, a sign of distress in
some mammals.)