Check your knee-jerk reflex.
Ask a partner to sit on the edge of a table with legs hanging freely.
Use the side of your hand to chop lightly at your partner's leg just below the kneecap (patella) at the patellar tendon.
Switch places and repeat the experiment.
What could you do to prevent this reflex from happening?
Research a disease that affects our reflexes, such as polio or amyotrophiclateral sclerosis (ALS, for short).
Read the inspiring stories of people who suffered from these diseases-for example, Franklin Delano Roosevelt, Lou Gehrig,and Stephen W.
Hawking.
Hold a pane of clear plastic or Plexiglas in front of your face, with your nose touching it.
Have someone throw a crumpled ball of paper at the plastic, aiming at your eyes.
Can you control your blinking reflex?
Hold a ruler horizontally just below your eyes, resting it on the cheekbones.
Close your eyes for a minute.
As you open them, have a friend shine a flashlight directly into your eyes and measure the distance the pupils contract.
Test to see if this pupillary reflex works with both eyes or just the eye exposed to the light.
Why does this reflex occur?