Chapter 16 Your Body Systems

1. Chapter 16 Your Body Systems Lesson 2 Your Muscular System Click for: >> Main Menu >> Chapter 16 Assessment Teacher’s notes are available in the notes section of this presentation. Next >>

2. The group of structures that give your body parts the power to move • muscularsystem The muscles attached to bones that enable you to move • skeletalmuscles The muscles found in organs, blood vessels and glands • smoothmuscles • cardiacmuscles Muscles found only in the walls of your heart

3. In this lesson, you will learn to • explainthe functions of the muscular system. • identifyhow muscle types differ. • describeways to keep your muscular system healthy.

4. Comparing and Contrasting Explain similarities and differences among the different muscle types in the lesson.

5. Your Muscles Your muscular system contains many muscles that perform different functions. muscular system The group of structures that give your body parts the power to move

7. Types of Muscles Skeletal muscles are the largest part of the body’s muscular system. skeletal muscles The muscles attached to bones that enable you to move Skeletal muscles are voluntary.

8. Types of Muscles The mouth, stomach, and lungs are all composed of smooth muscles. smooth muscles Muscles found in organs, blood vessels and glands Smooth muscles are involuntary.

9. Types of Muscles Cardiac muscles work continuously, even when you sleep. cardiac muscles Muscles found only in the walls of your heart Cardiac muscles are involuntary.

10. How Muscles Work There are two basic and opposite actions that account for all muscle movement. Contraction Extension The shortening of muscle fibers. The lengthening of muscle fibers. Muscle movement is triggered by impulses.

11. How Muscles Work 1 2 When you bend your arm, your biceps contract and pull on a bones of your lower arm. At the same time, the triceps extend. When you straighten your arm, your triceps contract and pull on the other bone in your lower arm. At the same time, the biceps extend.

12. Problems of the Muscular System Muscle strain is caused by small tears in a muscle or tendon. Strains usually occur in large muscles that have been overworked.

13. Problems of the Muscular System Muscular dystrophy is an inherited disease, and causes skeletal muscle tissue to gradually waste away.

14. Care of the Muscular System “Use it or lose it.” • Regular exercise helps maintain the natural tension in muscle fibers, called muscle tone. • Regular exercise also keeps the cardiac muscles healthy. • Eat well. • Warm up before exercising or playing sports. • Cool down after exercising or playing sports. • Use exercise or sports equipment properly. • Lift heavy objects properly.

15. Lesson 2 Review What I Learned VocabularyWhat are skeletal muscles? Name five of the major skeletal muscles in your body.

16. Lesson 2 Review What I Learned DescribeWhat are the functions of the muscular system?

17. Lesson 2 Review What I Learned ListGive two suggestions for keeping the muscular system healthy.

18. Lesson 2 Review Thinking Critically ApplyA teen is doing bench presses in the school’s weight room. During each repetition, he groans loudly. When you ask if he is in pain, he replies, “Yes—but it’s good pain.” How might you respond?

19. Lesson 2 Review Thinking Critically EvaluateA teen has been asked to carry some boxes of books to a classroom. He stoops over and pulls a box upward toward his chest. Should he continue lifting this way?

20. End of Chapter 16 Your Body Systems Lesson 2 Your Muscular System Click for: >> Main Menu >> Chapter 16 Assessment