1. Homeostasis
The process by which organisms keep internal conditions relatively constant despite changes in external conditions.

2. Before the Video
Why do we not respond to these changes in the same way as non-living materials?
How does the body know that these external changes are happening?
What sorts of things does the body do to keep itself from being changed by the environment? Are these things completely successful or does the environment cause changes?
Why is it necessary to keep the body at a certain temperature and to protect it from radiation?

3. After the Video
Once the race has started, the first changes that we see are increased heart rate and blood pressure. What is the purpose of this rapid increase in blood flow?
How does the body increase it’s oxygen supply?
The runners take in regular drinks of glucose and water. What do these two substances do for the body during the race?
How would the athlete know if the muscles were not receiving enough oxygen or food?

4. After the Video
What would happen if the temperature controls failed body temperature became abnormally high?
Why are runners wrapped in a thermal blanket at the end of the race?