• What is sound?
  Sound is waves of energy that are carried as vibrations through air, ...

• How loud is a whisper?
  A whisper is between 10 and 20 decibels. Some animals can detect much ...

• Why does sniffing help you detect smells better?
  The smell receptors are at the top of your nose, so when you sniff ...

• Why do some animals have keener smell?
  Many animals rely on smell for finding food and smelling attackers. ...

• Why do feces smell?
  Bacteria in the large intestine help to break down waste material, ...

• Which part of the body is least sensitive to touch?
  The back is one of the least sensitive areas of the body.

• Does taste matter?
  Unpleasant tastes can warn you when food has gone bad or is ...

• How do blind people use touch to see?
  Blind people can tell what something is like by feeling it. Outside, ...

• Which parts of the body are most sensitive to touch?
  Any part of the body that has lots of touch receptors is particularly ...

• Which parts of the body are most sensitive to heat?
  Your elbows and feet are more sensitive to heat than many other parts ...