The Electric Eel, Measured: teacher key

Electric Eels, grade 12 edition, written for 12th grade and up. The electric eel is a fish with a very strong shock. This book covers its three species, how its shock was measured and made, how it hunts alone and in groups, how it is related to other fish and how it breathes.

Read the book. Print this page for the key.

Questions and answers

1. How was the peak voltage of an eel's volley read in the 2019 study?
   • With an oscilloscope (answer)
   • With a ruler
   • With a thermometer
2. Why was the eel lying on a dry plastic sheet?
   • So the water was not part of the circuit (answer)
   • So it could sleep
   • So it could eat
3. In which waters does the eel's discharge not travel as far?
   • Clear highland water (answer)
   • Mineral-rich lowland water
   • Salt water
4. What happened when eels met a water-movement cue and an electric cue in different places?
   • They struck first toward the water-movement cue (answer)
   • They struck only the electric cue
   • They did not move
5. How often must an electric eel come to the surface for a breath?
   • At least every ten minutes (answer)
   • Once a week
   • Never
6. How many hours did scientists watch the eels in the Brazilian lake?
   • 7 hours
   • 72 hours (answer)
   • 720 hours

Words

• electrocytes: power cells
• oscilloscope: voltage-reading machine
• curare: nerve-blocking drug
• lineage: family line