1. Review What is the difference between a bone and a joint?
What are the four functions of the skeletal system?
Explain how a ball-and-socket joint works.
Name and explain one common skeletal or joint problem.

2. Review Why is bone marrow important?
What is the longest bone in your body?
What is the shortest bone in your body?
What do ligaments do?

3. Do you have a dictionary? Because these muscles are DEFINED.
The Muscular System
Do you have a dictionary? Because these muscles are DEFINED.

4. Vocabulary Muscle Muscular system Smooth muscle Cardiac muscle
Skeletal muscle
Tendons

5. Your Muscles
-The muscles that moves your body make up your muscular system.
-Any tissue that is made of cells or fibers that contract and expand to cause movement is called muscle.
-Your body has three types of muscle: smooth, cardiac, and skeletal.

6. Types of Muscles
Smooth Muscle - makes up many of your internal organs, including your stomach and intestines. Smooth muscle contractions move materials such as food through internal organs.

7. Types of Muscles
Cardiac Muscle - the muscle found in the heart. When cardiac muscle contracts, blood is pushed through the body.

8. Types of Muscles
Skeletal Muscle - muscle that is attached to bones. The muscles and bones are connected by tendons. When skeletal muscles contract, they pull on the bones they are attached to. This pulling causes your body to move. When skeletal muscles contract, they release energy, which helps maintain body temperature.

9. How Muscles Make You Move
-Many different skeletal muscles must work together to make your body move. Movement of a body part is the result of muscles pulling on the bones that form a joint.
-When a muscle contracts, the ends of the muscle are pulled toward the center of the muscle.
-Each end of the muscle is attached to a different bone. Therefore, as the muscle gets shorter, it pulls the two bones closer together.

10. How Muscles Make You Move
-When muscles contract, they can only pull the bones, not push them. To bend, or flex, the arm at the elbow, the biceps muscle contracts. When the biceps contracts, it pulls the bones of the forearm toward the shoulder.

11. How Muscles Make You Move
-The biceps can only bend the arm; it cannot straighten the arm. To straighten, or extend, the arm, the triceps muscle has to contract. The triceps is on the back of your arm. When the triceps contracts, it pulls the bones of the forearm away from the biceps. The movement straightens the arm.
See it in motion here

12. Common Muscular Problems
-Muscles do most of the work of the body.
-Because they are used so much, muscles can become tired and sore. They can also be strained and torn.
-To prevent muscle injuries, you should warm up, cool down, and stretch when exercising.

13. Muscular Dystrophy Description Treatment or prevention
a group of genetic diseases that lead to muscle weakness and in some cases destruction of skeletal muscle tissue
cannot be cured; may be treated with physical therapy and in some cases, surgery

14. Muscle Cramp Description Treatment or prevention
a sudden and usually painful contraction of a muscle; often happens at night or after exercise
usually requires no treatment; may be prevented by stretching before and after exercise

15. Strain Description Treatment or prevention
overstretching and possible tearing of a muscle due to overuse or misuse
treated with rest, ice, and wrapping the injury; may be prevented by stretching before exercise

16. Tendinitis Description Treatment or prevention
inflammation of a tendon caused by aging or excessive exercise
treated with rest, hot or cold compresses, and anti-inflammatory medications; may be presented by stretching and avoiding overuse

17. Shin splints Description Treatment or prevention
pain in the shin caused by damage or irritation to the muscles in the front of the lower leg
treated with rest, ice, and pain medication; may be prevented by not running on hard surfaces