Pretend that you have a slice of lemon in your hand.
Put the lemon in your mouth and bite down.
What’s happening to your body, particularly inside your mouth?
Now imagine that you have Styrofoam in your hand.
Stick your fingers into the Styrofoam to break off a piece. Then, put that in your mouth and bite down.
What’s happening to your body?
Finally, think of aluminum foil.
Crumple it up, put it in your mouth, and bite down.
Again, what’s happening?