The Sleep Test: teacher key

How Animals Sleep, grade 8 edition, written for 8th grade. An ostrich sleeps with its eyes open, and a frog freezes solid. Learn how scientists decide whether an animal is truly asleep.

Read the book. Print this page for the key.

Questions and answers

1. Which of these is part of the scientists' test for sleep?
   • The animal sleeps more after being kept awake (answer)
   • The animal has closed eyes
   • The animal lies down
2. What did the whales do when the boat came near?
   • Dove right away
   • Did not react until it touched one (answer)
   • Splashed the boat
3. Why did scientists need electrodes to study the ostriches?
   • A sleeping ostrich can look alert, so the readings showed when it was truly asleep (answer)
   • Ostriches cannot be seen
   • Ostriches never sleep
4. Why is it hard to say whether an insect is asleep?
   • Insects never move
   • Telling sleep from a sleep-like state is not always easy (answer)
   • Insects live underwater
5. How are wood frogs different from sleepers?
   • Their bodies freeze solid and the heart stops (answer)
   • They sleep upside down
   • They float upright
6. What does torpor mean here?
   • A low-energy winter state (answer)
   • A kind of boat
   • A bird's recorder

Words

• electrodes: sensor pads
• unihemispheric: one half-brain
• torpor: deep rest
• metabolism: body's energy use