Overview of Muscular System

Introduction: Now onto muscles! Let's face it, they are everywhere. Even in our faces! This section is going to introduce you as to the functions of our muscular system, the structure of it and how muscles work together. The picture below, from http://www.medicalook.com, not only shows you our muscular system, but it labels it as well!

*Function of Skeletal Muscles

1. Support the body

2. Make bones move

3. Help maintain a constant body temperature

4. Skeletal muscle contraction assists movement in cardiovascular and lymphatic

Vessels

5. Help protect internal organs and stabilize joints

*Skeletal Muscles of the Body

~Basic Structure

*Well organized

*Contains bundles of skeletal muscle fibers

*Muscles are covered with fascia, a type of connective tissue that extends

Beyond the muscle and becomes a tendon

* Tendon often goes past a joint then anchors a muscle to the bone

Above is a picture of a skeletal muscle with various parts labeled. It was found from http://www.medicalook.com.

~Work in Pairs

*Each muscle is concerned with the movement of only one bone

*Origin of a muscle is on stationary bone, the elbow joint for example, the origin is the scapula.

*Insertion of a muscle is on a moving bone, again, using the elbow joint, the insertion point is on the radius.

*When a muscle contracts, it pulls on tendon at insertion and the bone

Moves

*Muscles contract, they shorten

*Can only pull, cannot push so they work in opposite pairs

*One shortens while the other extends; bicep and tricep are a pair

*“Contraction of many cells makes whole muscle shorten, bringing

About body movements” (Slide 11, Movement)

Conclusion: Those are the basics of the skeletal system. Now it is time to take a closer look at the muscle contraction.