Where you live there is probably plenty of oxygen in the air. Up near the tops of very high mountains or up where airplanes fly, the atmosphere is thinner and there's not as much oxygen. Can human bodies handle this?

To learn more about the human body and high altitudes:

1. Go to the Mountain Top WWW Sheet and print it.

2. Visit this Web site. Read "Adapting to Less Oxygen:" Then complete the WWW Sheet.
    Going Up?

3. For more information, visit this Web site.
    Climbing Without Oxygen