The Muscular System OBJECTIVES ACTIVITIES. A. Completion

Transcription

1 C H A P T E R 9 The Muscular System OBJECTIVES After studying this chapter, you should be able to: 1. Describe the gross and microscopic anatomy of skeletal muscle. 2. Describe and compare the basic differences between the anatomy of skeletal, smooth, and cardiac muscle. 3. Explain the current concept of muscle contraction based on three factors: neuroelectrical, chemical, and energy sources. 4. Define muscle tone and compare isotonic and isometric contractions. 5. List factors that can cause muscles to malfunction, causing various disorders. 6. Name and identify the location of major superficial muscles of the body. ACTIVITIES A. Completion Fill in the blank spaces with the correct term. 1. Skeletal muscle is striated and. 2. Because their length is greater than their width, skeletal muscle cells are referred to as muscle. 3. The sarcolemma is surrounded by three types of connective tissue; they are the, the, and the. 4. A bands are the bands and I bands are the bands. 5. There are no cross-bridges in the. 6. The actual process of contraction occurs in the area called the. 7. Muscle fibrils are surrounded by membranes in the form of and. NAME: DATE:

2 134 Section 2 Chapter Exercises 8. These structures are referred to as the system. 9. An irregular curtain around each of the fibrils is the. 10. A motor unit is innervated by a(n). 11. Each motor unit in the muscle contains about 10 muscle cells. 12. A muscle fiber s membrane is surrounded by. 13. The two minerals causing a resting potential in a muscle are and. 14. The electrical potential is caused by a rapid influx of ions. 15. A muscle cell generating its own impulse is called its. 16. The two inhibitor substances surrounding the actin are and. 17. The substance negating their effect is. 18. The discoverer of the protein myosin was. 19. During contraction, the width of the A bands remains constant while the move closer. 20. The four sources of ATP for the energy of contraction are,,, and plus two ATP. 21. The all-or-none law states that a muscle contraction either or it. 22. A constant state of partial contraction is called. 23. The muscle that is nonstriated and found in hollow structures is. 24. Smooth muscle contraction occurs without the regular rearrangement of. 25. Cardiac muscle is under the control of the nervous system. 26. Fibrillation of cardiac muscle can result in. 27. Prime movers are. 28. assist the prime movers. 29. Muscles found directly under the skin are muscles. 30. is muscle pain. 31. Doctors of medicine take a therapeutic approach to medicine by placing greater emphasis on the relationship between the organs and the musculoskeletal system. 32. is a form of rheumatism but does not affect the joints. 33. Stepping on an old nail can transfer the bacterium causing to body tissues. B. Matching Match the term on the right with the definition on the left. 34. striated muscle a. resting potential 35. electrical cell membrane b. phosphocreatine 36. delicate connective tissue c. trapezius 37. individual bundles of cells d. myosin 38. surrounds whole muscle e. isotonic contraction 39. dark bands of protein f. origin 40. light of protein g. fibrillation 41. forms irregular curtain h. insertion

3 Chapter 9 The Muscular System inside minus outside plus i. skeletal 43. muscle impulse j. fascicle 44. contain ATP molecule k. action potential 45. only in muscle tissue l. sarcolemma 46. tension remains the same m. actin 47. rapid uncontrolled contraction n. zygomaticus 48. fixed attachment of muscle o. sarcoplasmic reticulum 49. movable attachment of muscle p. myosin filaments 50. prime mover q. endomysium 51. draw scalp backward r. epimysium 52. smiling muscle s. agonists 53. between the neck and clavicle t. occipitalis C. Key Terms Use the text to look up the following terms. Write the definition or explanation. 54. Action potential: 55. All-or-none law: 56. Antagonists: 57. Bands: 58. Contracture: 59. Cramps:

4 136 Section 2 Chapter Exercises 60. Electrical potential: 61. Fascicle: 62. Fibrillation: 63. H band: 64. Hypertrophy: 65. I band: 66. Insertion: 67. Isometric activity: 68. Isotonic activity: 69. Motor unit:

5 Chapter 9 The Muscular System Muscle twitch: 71. Myalgia: 72. Perimysium: 73. Phosphocreatine: 74. Plantar fasciitis: 75. Polio: 76. Psoas: 77. Rigor mortis: 78. Sarcotubular system: 79. Synergists: 80. T system:

6 138 Section 2 Chapter Exercises D. Labeling Exercise 81. Label the superficial muscles as indicated in Figure 9-1. E. Frontalis Orbicularis oculi A. Masseter F. G. B. C. H. Serratus anterior Rectus abdominis External oblique Linea alba Extensors of hand Flexors of hand and fingers Tensor fasciae latae Adductors of thigh Rectus femoris Sartorius D. Vastus medialis Patella Patellar ligament I. Tibialis anterior Soleus Tibia Peroneus longus Figure _09_Ch09_p indd 138 8/26/09 12:06:28 PM

7 Chapter 9 The Muscular System 139 A. B. C. D. E. F. G. H. I.

8 140 Section 2 Chapter Exercises 82. Label the superficial muscles as indicated in Figure 9-2. Occipitalis Sternocleidomastoid A. Seventh cervical vertebra D. Teres minor Infraspinatus Teres major Triceps brachii Rhomboid major B. Extensors of the hand and fingers C. Iliotibial tract Adductor magnus Biceps femoris Semitendinosus Gracilis Hamstrings Semimembranosus Gastrocnemius E. Peroneus longus Soleus Peroneus brevis Achille s tendon Figure _09_Ch09_p indd 140 8/26/09 12:06:29 PM

9 Chapter 9 The Muscular System 141 A. D. B. E. C. E. Coloring Exercise 83. Using Figure 9-3, color the gluteus maximus red, the biceps femoris (long head) blue, the biceps femoris (short head) yellow, the soleus green, and the calcaneal tendon orange. Figure 9-3

10 142 Section 2 Chapter Exercises F. Critical Thinking Answer the following questions in complete sentences. 84. Why should weightlifters do aerobic exercises for maximal physical fitness? 85. Explain two ways in which prolonged exertion during hot weather might cause muscles to malfunction. 86. Why does stimulation of nerves with electrical current help stave off muscle atrophy for a short period of time? 87. Explain the function of troponin and tropomyosin and what negates them. 88. On what does the strength of contractions depend? Explain. 89. Identify age-related changes in the muscle system. Explain what a sports medicine physician and a massage therapist can do to help.

11 Chapter 9 The Muscular System 143 G. Crossword Puzzle Complete the crossword puzzle using the following clues. ACROSS DOWN 3. Muscle found in hollow body structures 1. Injection site in the arm 7. Contraction when lifting a weight 2. Muscle inflammation 9. Skeletal muscle type 4. Thick protein filament in muscle cells 13. Muscle that closes the jaw 5. Constant state of partial contraction 14. Muscle pain 6. Inhibitor substance 15. Movable muscle attachment 8. Area between Z lines 16. Muscle that protrudes the lower lip 10. Muscle between the neck and clavicle 18. Electrically polarized cell membrane 11. Skeletal muscle bundles 25. Fixed muscle attachment 12. Muscle that raises the mandible 26. Muscle that moves the head 17. Muscles that assist the prime mover 28. Activity from tension against muscles 19. Neurotransmitter substance

12 144 Section 2 Chapter Exercises 29. Muscle that compresses the cheek 20. Rapid source of high-energy ATP 30. Thin filaments of protein 21. Increase in muscle size 22. Actin united with myosin 23. Smiling and laughing muscles 24. Rapid, uncontrolled contraction of heart cells 27. Prime mover CASE STUDY Nadea, a 35-year-old woman, tells the nurse practitioner at the local clinic that she is having problems holding her eyes open, smiling, and keeping her lips closed. She also states that she feels generally weak and easily fatigued. The nurse notes that Nadea has droopy eyelids and her face has little expression. QUESTIONS 1. What condition might be causing Nadea s symptoms of muscle fatigue and weakness? 2. What muscles does this disorder affect first? 3. Why does this condition develop? CHAPTER QUIZ 1. Muscles make up what percentage of body weight? a % d % b % e % c % 2. The longest and most slender muscle fibers are a. smooth d. uninucleated b. skeletal e. none of the above c. cardiac

13 Chapter 9 The Muscular System The entire muscle consists of a number of skeletal muscle bundles called a. perimysium d. actin b. myosin e. none of the above c. fasciculi 4. The sarcomere is the area between two a. Z bands d. A bands b. H bands e. none of the above c. I bands 5. The layer of areolar tissue covering the whole muscle trunk is called a. fascicle d. fascia b. fasciculi e. none of the above c. epimysium 6. The light bands are the a. A bands d. I bands b. Z lines e. none of the above c. H bands 7. The sarcotubular system is made up of the sarcoplasmic reticulum and the a. T system d. vesicle system b. H system e. none of the above c. sarcomere 8. On the average, a single motor nerve fiber innervates about how many muscle cells? a. 100 d. 250 b. 150 e. none of the above c Which of the following properties do muscle cells NOT possess? a. excitability d. elasticity b. conductivity e. none of the above c. contractility 10. Which of the following is a neurotransmitter? a. acetylcholine d. tropomyosin b. myosin e. none of the above c. actin

14 146 Section 2 Chapter Exercises 11. Muscle contraction is a. resting potential d. chemical potential b. electrical potential e. none of the above c. action potential 12. Calcium negates the effect of a. myosin d. sodium b. troponin e. none of the above c. actin 13. The sodium potassium pump restores a. resting potential d. chemical potential b. electrical potential e. none of the above c. action potential 14. Actin was discovered in a d b e. none of the above c Which of the following retains the same width during contraction? a. A bands d. Z lines b. I bands e. none of the above c. H bands 16. Which of the following moves apart at the end of a contraction? a. A bands d. Z lines b. I bands e. none of the above c. H bands 17. ATP is synthesized by all of the following EXCEPT a. glycolysis d. breakdown of phosphocreatine b. Krebs citric acid cycle e. none of the above c. electron transport 18. Which of the following is a rapid source of high-energy ATP for muscle contraction? a. glycolysis d. breakdown of phosphocreatine b. Krebs citric acid cycle e. none of the above c. electron transport

15 Chapter 9 The Muscular System Which of the following does a contraction NOT depend on? a. strength of stimulus d. temperature b. duration of stimulus e. none of the above c. speed of stimulus 20. Muscle remains at constant length but tension increases. What type of contraction is this? a. isotonic d. internal b. isometric e. none of the above c. tonal 21. Muscle shortens and thickens while tension remains constant. What type of contraction is this? a. isotonic d. internal b. isometric e. none of the above c. tonal 22. Some muscles will always be contracting while others are at rest. What type of contraction is this? a. isotonic d. external b. isometric e. none of the above c. tonal 23. Two of the three kinds of muscle in the body are uninucleated; they are a. smooth and cardiac d. visceral and striated b. smooth and skeletal e. none of the above c. cardiac and skeletal 24. Contraction is fastest in which kind of muscle? a. smooth d. visceral b. cardiac e. none of the above c. skeletal 25. The wide, flat attachment of muscle to bone is called a. ligament d. aponeurosis b. tendon e. origin c. insertion 26. The attachment of the biceps to the forearm is the a. agonist d. ligament b. insertion e. none of above c. origin

16 148 Section 2 Chapter Exercises 27. Muscles that straighten a joint are called a. agonists d. antagonists b. synergists e. origins c. insertions 28. An increase in muscle size is called a. atrophy d. myalgia b. myositis e. myasthenia gravis c. hypertrophy 29. Muscle weakness is called a. atrophy d. myalgia b. myositis e. myasthenia gravis c. hypertrophy 30. Inflammation of muscle tissue is called a. atrophy d. myalgia b. myositis e. myasthenia gravis c. hypertrophy 31. In the 1940s and 1950s many children developed paralysis of their limbs and had to be placed in iron lungs after contracting a. myalgia d. myositis b. plantar fasciitis e. polio c. tetanus 32. Which of the following muscles extends the thigh? a. adductor magnus d. adductor longus b. abductor brevis e. sartorius c. tensor fascia lata 33. The main muscles that close the jaw are the temporalis and the a. superior rectus d. buccinator b. masseter e. orbicularis oris c. pterygoid