11.5 The Muscular System Essential Question: How Does your Body Work?

1. Introduction to the Human Body Ms. De Los Rios 6h Grade 11.5 The Muscular System Essential Question: How Does your Body Work? What Muscles Are in Your Body? How Do Skeletal Muscles Work? Pgs. 434-439

2. Vocabulary 11.5 • Involuntary Muscle- A muscle that is not under conscious control. • Voluntary Muscle- A muscle that is under control. • Skeletal Muscle- A muscle that is attached to the bones of the skeleton and provides the force that moves the bones. • Tendon- Strong connective tissue that attaches muscle to the bone. • Smooth Muscle- Involuntary muscle found inside many internal organs of the body. • Cardiac Muscle- Inv. Muscle tissue found only in the heart. • Striated Muscle- A muscle that appears banded (skeletal muscle)

3. What Muscles are in Your Body? Pg.435 • Challenge: • Try doing anything without using your muscles! • Involuntary muscles, which are muscles that you cannot control, perform essential activities in your body. • Example: • such as keeping your heart beating • moving food through your digestive system. • By contrast, voluntary muscles allow you to move parts of your body in different ways when you want to. (muscles you can control) • Example: • Smiling • Writing • walking

4. The Muscular System pg 435 Muscle Use How is the person in each frame using involuntary and voluntary muscles?

5. What Muscles are in Your Body? Pg. 436 • Skeletal muscles are voluntary muscles that provide the force that moves your bones. • A tendon, which is a strong connective tissue, attaches skeletal muscles to a bone. • The tissue called cardiac muscle is found only in the heart and it’s an involuntary muscle. • Skeletal muscle and cardiac muscle are sometimes referred to as striated muscle, because of their banded appearance. • The inside of many internal body organs contain smooth muscle tissue that is not striated. • Examples: stomach & blood vessels • Smooth muscle and cardiac muscle are involuntary muscles.

6. The Muscular System pg. 436 Muscle Tissue There are three types of muscle tissue: skeletal, smooth, and cardiac.

7. The Muscular System pg. 436 Types of Muscle Tissue Identify the type of muscle tissue in each body structure. Smooth, Skeletal, or Cardiac

8. Did You Know? • Why do you shiver when you get chilled? You shiver when many of your skeletal muscles contract quickly again and again. When your muscles contract, they produce extra heat. So, by shivering, your body produces heat that warms you.

9. What Do Skeletal Muscles Work? Pg. 438 • Let me see you.. “Make a muscle!” • Skeletal muscles do their work by contracting (becoming shorter and thicker.) • Each time you move, more than one muscle is involved. Skeletal muscles work in pairs. • Muscle cells can only contract, not lengthen. While one muscle in a pair contracts, the other muscle in the pair relaxes to its original length. • Why it’s important to exercise regularly: • for maintaining the strength and flexibility of muscles. • Exercise makes individual muscle cells grow bigger, so the whole muscle becomes thicker and stronger. • Warming up before you exercise, increases the blood flow to your muscles, thus preparing the muscles for exercising.

10. The Muscular System pg. 43 Muscle Pairs When the arm is bent at the elbow, the biceps contracts while the triceps relaxes. What happens to each muscle when the arm is straightened?

11. What Do Skeletal Muscles Work? Pg. 439 • Sometimes, muscles can become injured. • A muscle strain occurs when muscles are overworked or overstretched. • After a long period of exercise, a skeletal muscle can cramp, or contract and stay contracted. • After injuring a muscle, it is important to follow medical instructions and rest the injured area so it can heal properly.