Chapter 16Body Systems

16-2 Muscular System

Muscular System

: Your muscular system is the group of structures that give your body the power to move.

Muscles pump blood through the body.Muscles move food through the digestive tract.Muscles control the movement of air in and out of the lungs.

MUSCLESDifferent types of muscles carry out different tasks.

Skeletal MuscleThe muscles attached to bones that enable you to move.

The largest part of the bodies muscular system.The muscles are voluntary. (You have the power to control them.)

Smooth MuscleThe muscles found in organs, blood vessels, and glands.

Found in the mouth, stomach, and lungs.These muscles are involuntary. (They operate without your awareness.)

Cardiac MuscleThe muscles found only in the walls of your heart.

They are involuntary.

How muscles work

Muscle movement is triggered by messages and impulses.

These impulses are sent to muscle fiber.

Muscle Fiber are narrow strands of tissue within muscle.

There are two basic and opposite actions that account for all muscle movement.

Contraction is the shortening of muscle fibers.Extension is the lengthening of muscle fibers.

CARE OF THE MUSCULAR SYSTEM

USE IT OR LOSE IT!Using your muscles helps to maintain the natural tension in the fibers. This natural tension is called muscle tone.

Staying active and eating well are the two best ways to keep your muscles toned.

Warm-up before sports and cool down afterward.

This will help prevent muscle strain.Using exercise and sports equipment properly can also prevent muscle injury.

Problems that may occur with your muscular system

Sore Muscles: a temporary condition caused by physical activity that stresses the muscle tissue beyond what it is accustomed to. Small microscopic tears occur in the muscle, These tears along with the inflammation that accompanies these tears, causes the pain.

Muscle Strain: an injury to a muscle that is caused by small tears to the muscle or tendon.

Muscular Dystrophy: a condition that is usually inherited and causes the skeletal muscle to gradually waste away.