​Human Body Systems
The Muscular System

The muscular system is responsible for movement in the body, whether it is voluntary or involuntary. Consider your reflexes. When someone taps you on the knee, the leg jumps without you thinking about it. These are involuntary movements. Voluntary movements include things like walking and talking.
​
  • There are over 30 muscles in the human hand.
  • our lips are red because the skin is so thin that you can see the muscles below it.
  • Muscles make up roughly one-third of a person's body weight.
  • You get goosebumps when you're cold because tiny muscles beneath the skin contract to close the pores on the skin and prevent some body heat from escaping. This causes the hair on your skin to stand up.
  • It takes 17 muscles to smile and 43 to frown.
  • The tongue is the strongest muscle in the body.