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Guide Index

Big Picture

Spider Canyon

Frozen Alive

Ultimate Speed

Hidden Depths

High Anxiety

Viewer Challenge
in the classroom
TEACHING GUIDES


GOING TO EXTREMES: Answers to Viewer Challenge



SPIDER CANYON

1. The female funnel web spider senses vibration patterns of the prey when it touches her web.

2. (b.) The hybrid spider offspring of aggressive males from the desert and the less aggressive spiders from the river are super-aggressive.



FROZEN ALIVE

3. Antifreeze proteins in its blood enables the winter flounder to survive the cold temperature of sea water.

4. (a.) Glucose enables the wood frog to freeze and thaw.



ULTIMATE SPEED

5. (d.) When the cheetah is running, it gets extra power from energy stored in its back.

6. The cheetah is a sprinter and is anaerobic. The pronghorn is a long-distance runner with great endurance and is aerobic.



HIDDEN DEPTHS

7. "Marine snow" is made of junk, detritus and dust from the upper layer of ocean that drifts down.

8. (a & d.) The ocean at the middle depths contains low levels of oxygen and light.



HIGH ANXIETY

9. (c.) The air at high altitudes causes problems for climbers because it contains less oxygen.

10. Night is the most dangerous time on the mountain for climbers susceptible to altitude sickness.









 

Scientific American Frontiers
Fall 1990 to Spring 2000
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