1. The Muscular System
Chapter 21-3

2. Science Words Muscle Voluntary muscle Involuntary muscle
Skeletal muscle
Tendon
Smooth muscle
Cardiac muscle

3. Moving the human body Muscles of the body
Muscle-an organ that contracts and gets shorter- this provides the force to move your body parts.
Muscles of the
body

4. Muscle Control Voluntary muscles- muscles that you are able to control
Examples are leg and arm muscles
Involuntary Muscles- you can not move them consciously. They just keep working
Examples- heart

6. Types of Muscles-skeletal
Skeletal Muscles-muscles that move bones
Attached to bones by tendons
Most numerous in the body
Look striped or striated
Voluntary muscles

7. Types of Muscles-Smooth Muscles
Smooth muscles- nonstriated
Involuntary
Move the internal organs
Contract and relax slowly
Example- small intestine

8. Types of Muscles-Cardiac Muscle
Cardiac muscle-found only in the heart
Involuntary
Striations
Contracts about 70 times a minute every day of your life.

9. Types of Muscles
Types of muscles

10. How Muscles Work How muscles work
Skeletal muscles-when one muscles contracts- another muscle relaxes
Muscles always pull- never pushes
Muscles use glucose
Produce thermal energy when they contract
Muscles that are not exercised become smaller
How muscles work

11. Muscles and bones work together
Working together
A review