Three Reflexes Side by Side: teacher key

Hiccups, Sneezes and Yawns, grade 11 edition, written for 11th grade. Hiccups, sneezes and yawns each move air, and each is run by nerves and the brain. Compare how they work, where they began and what nobody has yet explained.

Read the book. Print this page for the key.

Questions and answers

1. What does the glottis do in a hiccup?
   • It closes and cuts off the sudden breath (answer)
   • It makes the diaphragm jerk
   • It widens to three times its size
2. Which nerve does a sneeze start from, in the nose?
   • The vagus nerve
   • The phrenic nerve
   • The trigeminal nerve (answer)
3. What do hiccups, sneezes and yawns have in common in the way they move air?
   • Each one is the same kind of cough
   • Each involves a breath, in or out (answer)
   • None of them uses the throat
4. What did the Vienna study suggest about contagious yawning in a group?
   • It could help the whole group stay alert (answer)
   • It makes the group sleep
   • It happens only in winter
5. What do researchers say about the oxygen idea for yawning?
   • It was proven
   • It is the main theory today
   • Studies did not support it (answer)
6. What does arousal mean in the arousal theory of yawning?
   • Waking up the brain (answer)
   • A loud noise
   • Cooling the blood

Words

• reflex: automatic body action
• diaphragm: breathing muscle
• glottis: throat gap
• trigeminal: face nerve
• empathy: sharing feelings
• brainstem: brain base