2. Lesson 3 How can you keep your muscles flexible and strong? The Muscular System Proper warm-up and stretching before and cool-down after any physical activity keeps your muscles flexible and strong.

3. Lesson 3 Describe the functions of the muscular system Examine the different types of muscles in the body and the effects of health behaviors on the muscular system List problems of the muscular system In this lesson, you will learn to: Lesson Objectives

4. Lesson 3 Functions of the Muscular System Voluntary and Involuntary Muscles When you sleep, muscles help you breathe, make your heart beat, and move food through your digestive system. These involuntary processes happen without your consciously controlling them. When you play the piano or a video game, you are using muscles that are under conscious, or voluntary, control. Without the use of both voluntary and involuntary muscles, you would be unable to perform any of these activities.

5. Lesson 3 Nerve Impulses and Muscle Fibers A muscle is made up of hundreds of long cells called fibers. Muscles work by means of two complementary, or opposing, actions — contraction and extension. Muscle contraction is triggered by nerve impulses. Some nerves provide impulses for many muscle fibers. In other areas, a single nerve may provide impulses to only two or three muscle fibers. Structure of the Muscular System

6. Lesson 3 Types of Muscles Smooth Muscles Skeletal Muscles Cardiac Muscles Structure of the Muscular System Smooth musclesSmooth muscles can be found in the lining of the blood vessels, the digestive tract, the passageways that lead into the lungs, and the bladder. Smooth muscles are under involuntary control.

7. Lesson 3 Muscle Contraction and Bone Movement Click image to view movie. Structure of the Muscular System

8. Lesson 3 Regular physical activity is the best way to keep your muscles strong and healthy. Regular physical activity helps keep muscles toned and healthy.muscles toned Practicing good posture strengthens back muscles. Wearing safety equipment and appropriate clothing can protect muscles during physical activity. Care of the Muscular System Structure of the Muscular System

9. Lesson 3 Injury-Related Muscle Problems Bruise Muscle Strain/Sprain Tendonitis Hernia Muscular Dystrophy Problems of the Muscular System

10. Lesson 3 Bruise A bruise is an area of discolored skin that appears after an injury causes the blood vessels beneath the skin to rupture and leak. Swelling can be reduced with an ice pack. Problems of the Muscular System

11. Lesson 3 Muscle Strain or Sprain A strained muscle results when a muscle is stretched or partially torn as a result of overexertion. Strains are usually treated by using the R.I.C.E. (rest, ice, compression, elevation) procedure. A sprain is an injury to the ligament in a joint, and it requires medical treatment. Problems of the Muscular System

12. Lesson 3 Tendonitis Tendonitis can be caused by injury, overuse, or aging.Tendonitis Treatment includes rest, anti-inflammatory medication, or ultrasound. Problems of the Muscular System

13. Lesson 3 Hernia A hernia can result from straining to lift a heavy object.hernia Hernia repair usually requires surgery. Problems of the Muscular System

14. Lesson 3 Muscular Dystrophy Muscular dystrophy is an inherited disorder in which skeletal muscle fibers are progressively destroyed. There is no cure, but with early detection muscle weakness can be delayed through exercise programs. Problems of the Muscular System

15. Lesson 3 Quick Review Q. Muscles work independently of other body systems. True False Choose the appropriate option.

16. Lesson 3 Click Next to attempt another question. Quick Review - Answer A. False. Muscles work with respiratory, cardiovascular, and digestive systems.

17. Lesson 3 Quick Review Q. A type of striated muscle that forms the wall of the heart is called: Choose the appropriate option. 1.Skeletal muscle 2.Long muscle 3.Smooth muscle 4.Cardiac muscle

18. Lesson 3 Click Next to attempt another question. Quick Review - Answer A. 4. Cardiac muscle The cardiac muscle is responsible for the contraction of the heart and is the most important part of the cardiovascular system.

19. Lesson 3 Choose the appropriate option. 1.Tendonitis 2.Muscle strains and sprains 3.Bruises 4.Hernia 5.All of the above Quick Review Q. Problems of the muscular system include:

20. Lesson 3 Click Next to attempt another question. A. 4. All of the above. The problems of muscular system include all of the following: tendonitis, muscle strains and sprains, bruises, and hernia. Quick Review - Answer

21. Lesson 3 End of Lesson 3 Click Home to view the Main menu.

22. Lesson 3 Types of Muscles Smooth musclesSmooth muscles can be found in the lining of the blood vessels, the digestive tract, the passageways that lead into the lungs, and the bladder. Smooth muscles are under involuntary control. Smooth muscles are muscles that act on the lining of passageways and internal organs. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

23. Lesson 3 Types of Muscles Most of your muscle tissue is made up of skeletal muscle, and almost all skeletal muscles are under voluntary control. skeletal muscle Skeletal muscles often work together, undergoing opposing actions to produce movement. FlexorFlexor and extensor are opposing skeletal muscles.extensor Skeletal muscles are attached to bone and cause body movements. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

24. Lesson 3 Types of Muscles Most of your muscle tissue is made up of skeletal muscle, and almost all skeletal muscles are under voluntary control. skeletal muscle Skeletal muscles often work together, undergoing opposing actions to produce movement. FlexorFlexor and extensor are opposing skeletal muscles.extensor The flexor is the muscle that closes a joint. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

25. Lesson 3 Most of your muscle tissue is made up of skeletal muscle, and almost all skeletal muscles are under voluntary control. skeletal muscle Skeletal muscles often work together, undergoing opposing actions to produce movement. FlexorFlexor and extensor are opposing skeletal muscles.extensor Types of Muscles The extensor is the muscle that opens a joint. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

26. Lesson 3 Types of Muscles The involuntary cardiac muscles are responsible for the contraction of your heart.cardiac muscles The heart contracts rhythmically about 100,000 times each day to pump blood throughout your body. Cardiac muscle is a type of striated muscle that forms the wall of the heart. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

27. Lesson 3 Regular physical activity is the best way to keep your muscles strong and healthy. Regular physical activity helps keep muscles toned and healthy.muscles toned Practicing good posture strengthens back muscles. Wearing safety equipment and appropriate clothing can protect muscles during physical activity. Muscle tone is the natural tension in the fibers of a muscle. Structure of the Muscular System Care of the Muscular System

28. Lesson 3 Tendonitis can be caused by injury, overuse, or aging.Tendonitis Treatment includes rest, anti-inflammatory medication, or ultrasound. Tendonitis Tendonitis is the inflammation of a tendon. Problems of the Muscular System

29. Lesson 3 Hernia A hernia can result from straining to lift a heavy object. Hernia repair usually requires surgery. A hernia occurs when an organ or tissue protrudes through an area of weak muscle. Problems of the Muscular System

30. Lesson 3 Cardiac Muscles Types of Muscles Most of your muscle tissue is made up of skeletal muscle, and almost all skeletal muscles are under voluntary control. skeletal muscle Skeletal muscles often work together, undergoing opposing actions to produce movement. FlexorFlexor and extensor are opposing skeletal muscles.extensor Structure of the Muscular System Smooth Muscles Skeletal Muscles

31. Lesson 3 Types of Muscles The involuntary cardiac muscles are responsible for the contraction of your heart.cardiac muscles The heart contracts rhythmically about 100,000 times each day to pump blood throughout your body. Structure of the Muscular System Smooth Muscles Skeletal Muscles Cardiac Muscles

32. Lesson 3 A. Correct! Muscles work with respiratory, cardiovascular, and digestive systems. Click Next to attempt another question. Quick Review - Answer

33. Lesson 3 You have answered the question incorrectly. Go back to try again, or click Next to view the correct answer. Quick Review - Answer

34. Lesson 3 A. Correct! The cardiac muscle is responsible for the contraction of the heart and is the most important part of the cardiovascular system. Click Next to attempt another question. Quick Review - Answer

35. Lesson 3 You have answered the question incorrectly. Go back to try again, or click Next to view the correct answer. Quick Review - Answer

36. Lesson 3 A. Correct! All of the above. Click Next to attempt another question. Quick Review - Answer

37. Lesson 3 You have answered the question incorrectly. Go back to try again, or click Next to view the correct answer. Quick Review - Answer