1. Muscular System Chapter 7 Movement Unit

2. 2 Fig. 7.1 Review:

3. 3 Functions of Skeletal Muscle:  Support the body (opposes the force of gravity)  Make bones and other body parts move  Maintain a constant body temperature  Assist movement in cardiovascular and lymphatic vessels  Protect internal organs and stabilize joints

4. 4 Microscopic Anatomy of Skeletal Muscle:  What do we already know from histology? Striations.  Arrangement of myofilaments in a muscle fiber (cell).  Normal cell with some specialized terms for cell parts. (Plasma membrane = sarcolema, endoplasmic reticulum = sarcoplasmic reticulum)

5. 5 Microscopic Anatomy of Muscle (Sarcoplasmic Reticulum)  Remember this is the ER for muscle cells.  Sarcoplasmic reticulum has specialized pockets to store calcium ions (Ca 2+ ) which is essential for muscle contraction.  The sarcoplasmic reticulum encases hundreds of myofibrils which allow for contraction of the muscle cell.

6. 6 Microscopic Anatomy of Muscle:  Myofibrils run the length of the muscle fiber.  Striations are formed by the placement of these myofibrils forming sarcomeres.  Sarcomeres contain two types of protein fibers: actin (thin and intertwined) and myosin (thick and shaped like golf club).

7. 7 Fig. 7.3a

8. 8 Fig. 7.3b

9. 9 Microscopic Anatomy of Muscle:  Sliding Filaments – when the muscles are triggered by motor nerve cells, impulses travel down the T-tubule of the sarcomere (see previous picture). Calcium is then released from the sarcoplasmic reticulum. This causes the sarcomere to shorten. The actin slides across the myosin. ATP provides the power for this contraction.

10. 10 Fig. 7.4

11. 11 Fig. 7.5

12. 12 Macroscopic Anatomy of Muscle:  3 Layers of connective tissue are part of each muscle: Epimysium – surrounds entire muscle, dense layer of collagen fibers. Perimysium – divides muscle into compartments called fascicles. Endomysium – delicate connective tissue that surrounds each muscle cell or fiber.  Where these connective tissues run together at the end of muscles they form tendons or aponeurosis.

13. 13 Fig. 7.2a

14. 14 Fig. 7.5a

15. 15 Fig. 7.5b

16. 16 Fig. 7.6

17. 17 Fig. 7.7

18. 18 Fig. 7.8

19. 19 Fig. 7.8a

20. 20 Fig. 7.8b

21. 21 Fig. 7.8c

22. 22 Fig. 7.9

23. 23 Fig. 7.10

24. 24 Fig. 7.10a

25. 25 Fig. 7.10b

26. 26 Fig. 7.11

27. 27 Fig. 7.12

28. 28 Fig. 7.13

29. 29 Fig. 7.14

30. 30 Fig. 7.15

31. 31 Fig. 7.16a

32. 32 Fig. 7.16ab

33. 33 Fig. 7.16b

34. 34 Fig. 7.16c

35. 35 Fig. 7.16cd

36. 36 Fig. 7.16d

37. 37 Fig. 7.17

38. 38 Fig. 7.18

39. 39 Fig. 7.19

40. 40 Fig. 7.20

41. 41 TA p120a

42. 42 TA p120b

43. 43 TA p120c

44. 44 Fig. 7.1

45. 45 Fig. 7.2

46. 46 Fig. 7.2a

47. 47 Fig. 7.2b

48. 48 Fig. 7.2c

49. 49 Fig. 7.3a

50. 50 Fig. 7.3b

51. 51 Fig. 7.4

52. 52 Fig. 7.5

53. 53 Fig. 7.5a

54. 54 Fig. 7.5b

55. 55 Fig. 7.6

56. 56 Fig. 7.7

57. 57 Fig. 7.8

58. 58 Fig. 7.8a

59. 59 Fig. 7.8b

60. 60 Fig. 7.8c

61. 61 Fig. 7.9

62. 62 Fig. 7.10

63. 63 Fig. 7.10a

64. 64 Fig. 7.10b

65. 65 Fig. 7.11

66. 66 Fig. 7.12

67. 67 Fig. 7.13

68. 68 Fig. 7.14

69. 69 Fig. 7.15

70. 70 Fig. 7.16a

71. 71 Fig. 7.16ab

72. 72 Fig. 7.16b

73. 73 Fig. 7.16c

74. 74 Fig. 7.16cd

75. 75 Fig. 7.16d

76. 76 Fig. 7.17

77. 77 Fig. 7.18

78. 78 Fig. 7.19

79. 79 Fig. 7.20

80. 80 TA p120a

81. 81 TA p120b

82. 82 TA p120c

83. 83 Table 7.1

84. 84 Table 7.2

85. 85 Table 7.3

86. 86 Table 7.4

87. 87 Table 7.5

88. 88 Table 7A