1. Honors Anatomy Nov 16 SAP2b: Explain how the skeletal structures provide support and protection for tissues, and function together with the muscular system to make movements Warm up: What are the 3 types of muscles? How are they different? Classwork: Intro to muscles ppt notes (pg183-187) Closing: fill in graphic organizer to compare/contrast 3 types of muscles/ draw & label skeletal muscle pg 185

2. The Muscular System

3. or “Everything you ever wanted to know about Muscles, but were afraid to ask” !!!

4. Did you know that ? -more than 50% of body weight is muscle ! -And muscle is made up of proteins and water

6. There are four characteristics associated with muscle tissue:  Excitability  Contractility  Extensibility  Elasticity - Tissue can receive & respond to stimulation - Tissue can shorten & thicken - Tissue can lengthen - After contracting or lengthening, tissue always wants to return to its resting state

7. The characteristics of muscle tissue enable it to perform some important functions, including:  Movement – both voluntary & involuntary  Maintaining posture  Supporting soft tissues within body cavities  Guarding entrances & exits of the body  Maintaining body temperature

8. Info About Muscles Only body tissue able to contract create movement by flexing and extending joints Body energy converters (many muscle cells contain many mitochondria)

9. The Muscular System Muscles are responsible for all movement of the body There are three basic types of muscle –Skeletal –Cardiac –Smooth

10. 3 Types of Muscles

11. Three types of muscle SkeletalCardiacSmooth

12. Muscle video Dr. Parker Muscle Video

13. Classification of Muscle Skeletal- found in limbs Cardiac- found in heart Smooth- Found in viscera Striated, multi- nucleated Striated, 1 nucleus Not striated, 1 nucleus voluntaryinvoluntary

14. Characteristics of Muscle Skeletal and smooth muscle are elongated Muscle cell = muscle fiber Contraction of a muscle is due to movement of microfilaments (protein fibers) All muscles share some terminology –Prefixes myo and mys refer to muscle –Prefix sarco refers to flesh

15. Shapes of Muscles Triangular- shoulder, neck Spindle- arms, legs Flat- diaphragm, forehead Circular- mouth, anus

16. Skeletal Muscle Most are attached by tendons to bones Cells have more than one nucleus (multinucleated) Striated- have stripes, banding Voluntary- subject to conscious control Tendons are mostly made of collagen fibers Found in the limbs Produce movement, maintain posture, generate heat, stabilize joints

17. Structure of skeletal muscle Each cell (fiber) is long and cylindrical Muscle fibers are multi-nucleated Typically 50-60mm in diameter, and up to 10cm long The contractile elements of skeletal muscle cells are myofibrils

18. Skeletal muscle - Summary Voluntary movement of skeletal parts Spans joints and attached to skeleton Multi-nucleated, striated, cylindrical fibres

19. Smooth Muscle No striations Spindle shaped Single nucleus Involuntary- no conscious control Found mainly in the walls of hollow organs

20. Smooth muscle Lines walls of viscera Found in longitudinal or circular arrangement Alternate contraction of circular & longitudinal muscle in the intestine leads to peristalsis

21. Structure of smooth muscle Spindle shaped uni-nucleated cells Striations not observed Actin and myosin filaments are present( protein fibers)

22. Smooth muscle - Summary Found in walls of hollow internal organs Involuntary movement of internal organs Elongated, spindle shaped fibre with single nucleus

23. Cardiac Muscle Striations Branching cells Involuntary Found only in the heart Usually has a single nucleus, but can have more than one

24. Cardiac muscle Main muscle of heart Pumping mass of heart Critical in humans Heart muscle cells behave as one unit Heart always contracts to it’s full extent

25. Structure of cardiac muscle Cardiac muscle cells (fibres) are short, branched and interconnected Cells are striated & usually have 1 nucleus Adjacent cardiac cells are joined via electrical synapses (gap junctions) These gap junctions appear as dark lines and are called intercalated discs

26. Cardiac muscle - Summary Found in the heart Involuntary rhythmic contraction Branched, striated fibre with single nucleus and intercalated discs

27. Muscle Control Type of muscle Nervous control Type of control Example Skeletal Controlled by CNS Voluntary Lifting a glass Cardiac Regulated by ANS Involuntary Heart beating Smooth Controlled by ANS Involuntary Peristalsis

28. Honors Anatomy Nov 17 SAP2b: Explain how the skeletal structures provide support and protection for tissues, and function together with the muscular system to make movements Warm up: Why is it necessary for cardiac and smooth muscle to be involuntary? Classwork: Gross anatomy of skeletal muscle ppt notes; pg 185 Closing: Draw/ label skeletal muscle gross anatomy pg 185.

29. Introductory Questions Where is skeletal muscle found in your body? Attached to bone. (Smooth muscle lines organs, and cardiac muscle is found in the heart.) What is the function of skeletal muscle? Voluntary movement Stability (posture) Communication (facial expression, speech) Control of body openings Heat production- 85% of body heat is generated by muscles providing the proper environment for enzymes and therefore metabolism

30. Types of Responses Twitch- –A single brief contraction –Not a normal muscle function Tetanus –One contraction immediately followed by another –Muscle never completely returns to a relaxed state –Effects are compounded

31. Where Does the Energy Come From? Energy is stored in the muscles in the form of ATP ATP comes from the breakdown of glucose during Cellular Respiration This all happens in the Mitochondria of the cell When a muscle is fatigued (tired) it is unable to contract because of lack of Oxygen

32. Exercise and Muscles Isotonic- muscles shorten and movement occurs ( most normal exercise) Isometric- tension in muscles increases, no movement occurs (pushing one hand against the other)

33. How are Muscles Attached to Bone? Origin-attachment to a movable bone Insertion- attachment to an immovable bone Muscles are always attached to at least 2 points Movement is attained due to a muscle moving an attached bone

34. Muscle Attachments Origin Insertion

35. Skeletal Muscle Attachments  Epimysium blends into a connective tissue attachment  Tendon – cord-like structure  Aponeuroses – sheet-like structure  Sites of muscle attachment  Bones  Cartilages  Connective tissue coverings

36. Connective Tissue Wrappings of Skeletal Muscle  Epimysium – covers the entire skeletal muscle  Fascia – on the outside of the epimysium

37. Connective Tissue Wrappings of Skeletal Muscle  Endomysium – around a single muscle fiber  Perimysium – around a fascicle (bundle) of fibers

38. Word Parts/Meanings Fascia- band or bundle Epi-upon Peri- around Endo- inner Mys- muscle Sarco-flesh Lemma- husk

39. Gross Anatomy of Skeletal Muscle Turn to page 185 in text book and draw/label the diagram of a skeletal muscle. Be very detailed.

41. Structures of a skeletal muscle fiber

42. A Sarcomere

43. Twizzler analogy Many packages of Twizzlers = Fascicle Find a Fascicle on your diagram.

44. Twizzler analogy 2 1 package of Twizzlers = Muscle fiber The packaging = Sarcolemma

45. Twizzler analogy 3 1 bundle of twizzlers = myofibril

46. Twizzler analogy 4 1 Twizzler strand = Filament

47. Compare the Muscle Fiber to Pull and Peel Twizzlers How amazing is that?

51. Flexion Types of Musculo-Skeletal Movement

52. Extension

53. Hyperextension

54. Abduction, Adduction & Circumduction

55. Rotation

56. More Types of Movement…… Inversion- turn sole of foot medially Eversion- turn sole of foot laterally Pronation- palm facing down Supination- palm facing up Opposition- thumb touches tips of fingers on the same hand

57. The Skeletal Muscles There are about 650 muscles in the human body. They enable us to move, maintain posture and generate heat. In this section we will only study a sample of the major muscles.

58. Sternocleidomastoideus Flexes and Rotates Head

59. Masseter Elevate Mandible

60. Temporalis Elevate & Retract Mandible

61. Trapezius Extend Head, Adduct, Elevate or Depress Scapula

62. Latissimus Dorsi Extend, Adduct & Rotate Arm Medially

63. Deltoid Abduct, Flex & Extend Arm

64. Pectoralis Major Flexes, adducts & rotates arm medially

65. Biceps Brachii Flexes Elbow Joint

66. Triceps Brachii Extend Elbow Joint

67. Rectus Abdominus Flexes Abdomen

68. External Oblique Compress Abdomen

69. External Intercostals Elevate ribs

70. Internal Intercostals Depress ribs

71. Diaphragm Inspiration

72. Forearm Muscles Flexor carpi—Flexes wrist Extensor carpi—Extends wrist Flexor digitorum—Flexes fingers Extensor digitorum—Extends fingers Pronator—Pronates Supinator—Supinates

73. Gluteus Maximus Extends & Rotates Thigh Laterally

74. Rectus Femoris Flexes Thigh, Extends Lower Leg

75. Gracilis Adducts and Flexes Thigh

76. Sartorius Flexes Thigh, & Rotates Thigh Laterally

77. Biceps Femoris Extends Thigh & Flexes Lower Leg

78. Gastrocnemius Plantar Flexes Foot & Flex Lower Leg

79. Tibialis Anterior Dorsiflexes and Inverts Foot