AIM
To measure the breathing rate changes in a person subjected to a cold and warm environment.
HOW DOES IT WORK?
Time allocation: 45 Min
The body uses certain systems to regulate when the body is too cold or too hot. It is expected that when one is hot heat is lost through panting, which is a form of hyperventilation. In cold temperature the body’s functions slow-down in attempt to save energy reserves in this way a person reduces their respiratory rate. This is an important factor at play during hyperthermia.
In the first part of the experiment we will attempt to drop a person’s core temperature, which will result in the body wanting to compensate for this. The body will try and preserve energy initially and this will be seen in a decrease in respiratory rate.
In the second part of the experiment the person’s core temperature will be raised, which result in the body wanting to lose the extra heat energy. In respiration this will be seen as hyperventilation through panting, like a dog. This causes evaporation through the mouth which causes the body to cool.
MATERIALS
- 1 x Space blanket
- 1 x Stopwatch
- 1 x oral thermometer
- 1 x clicking counter
- 1 flat bucket that fits a person’s feet
- Tap water
- Bag of ice
- Lots of warm clothing
- Heater
METHOD:
- Fill the plastic basin with cold water and pour the bag of ice into the water
- The test subject’s breathing rate must now be measured for 1 minute. This is your 0 min measurement. Also measure the person’s temperature by lacing thermometer under their tongue.
- The test subject must now place his/her feet in the cold water filled bucket, it is best to remain seated throughout the experiment.
- After 5 min measure the test subject’s breathing rate and oral temperature. Note person must not talk or breathe through mouth during this experiment.
- Repeat step 4 a further 5 more times (so that the experiment spans 30min).
- A different test subject must now be allocated
- Measure the amounts of breaths taken for 1 min. This will be your rate at 0min. Also take the person’s temperature.
- The test subject must place all extra clothing on, wrap the person in the space blanket with the shiny side inside and place the person directly in front of the heater.
- After 5 min count the person’s breaths for 1 minute and take their temperature. Note that the person does not have to keep their mouth closed but it will help insulate their body heat as much as possible.
- Repeat step 9 a further 5 times (so that the final time is 30 min).
OBSERVATIONS
Record the observation in the printable student practical.
Cold experiment:
Heat Experiment:
PRECAUTIONS:
- It is recommended that the experiment is prepared well in advance.
- The experiment should be performed on a day that is neither hot nor cold in temperature.
- People with heart or respiratory conditions should not be considered as test subjects as this may aggravate their condition.