AGR 282 Quiz 4

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AGR 282 Quiz 4
2013-10-16 01:02:56
Muscular System

Muscles, Muscle contraction/relaxation steps
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  1. Four types of tissue
    • Epithelial
    • Connective
    • Muscle
    • Nervous
  2. 3 types of muscle tissue
    • Skeletal 
    • Smooth
    • Cardiac
  3. Skeletal Muscle Attachment
    • Most muscles attach to bones by tendons
    • Some muscles attach to bone or other muscle by sheets of connective tissues
  4. Sheets of connective tissue
    Aponeuroses eg linea alba - runs lengthwise between muscles on abdomen (ventral midline)
  5. Origin of Muscle
    • Attachment site that is more stable 
    • Does not have much movement when muscle contracts
  6. Insertion of muscle
    Attachment site that undergoes most of the movement when a muscle contracts
  7. Flexation
    To bend, joint movement that decreases angle between bones
  8. Extension
    To extend, joint movement that increases the angle between bones
  9. Abduction
    Movement that pulls a structure or part away from the midline
  10. Adduction
    Movement that pulls structure or part toward the midline
  11. Prime Mover (Agonist)
    Muscle or muscle group that directly produces desired movement
  12. Antagonist
    Muscle or muscle group that directly opposes action of prime mover
  13. Synergist
    Muscle that contracts at the same time as prime mover and assists in carrying out its action
  14. Fixator
    Muscle that contracts to help stabilize joints
  15. Cutaneous Muscles
    • Skin muscles 
    • located just beneath skin 
    • Little to no attachment to bones 
    • Thin, broad muscles
    • Twitch the skin
  16. Head and Neck Muscles
    • Control facial expressions 
    • Enable chewing 
    • Move sensory structures (eyes and ears)
    • Support and movement of heat and neck
  17. Masseter Muscle
    • In cheek area
    • powerful chewing muscle
    • Mastication: chewing
    • Closes the jaw
  18. Splenius and Trapezius Muscles
    Extend (raise) the head and neck
  19. Brachiocephalicus Muscle
    • Extend (raise) the head and neck
    • Pull front leg forward 
    • Extend shoulder
  20. Sternocephalicus Muscle
    Flexes or lowers the head and neck
  21. Abdominal Muscles
    • Support abdominal organs 
    • Flex (arch) the back
    • Straining 
    • Respiration
  22. Straining of Abdominal Muscles
    • Expulsion of Feces from rectum (defication)
    • Expulsion of Urine from bladder (urination)
    • Expulsion of Fetus from uterus (parturition)
    • Examples: Vomiting and regurgitation
  23. Examples of Abdominal Muscles (from outside in)
    • External abdominal oblique 
    • Internal abdominal oblique 
    • Rectus abdominis 
    • Transversus abdominis
    • Paired muscles
    • Sides come together
  24. Thoracic Limb Muscles
  25. Latissimus Dorsi
    • Broad, triangular muscle
    • Flexes shoulder 
    • Draw limb caudally
    • Propels the body forward
  26. Pector Muscles
    • One superficial muscle 
    • One deep muscle 
    • Act as adductors (inward)
  27. Deltoid
    • Triangular 
    • Act as abductor (outward)
  28. Brachium
    • Upper arm region 
    • 2 muscles to know (biceps brachii and triceps brachii)
  29. Biceps Brachii
    • 2 heads
    • Flexes (bends) elbow
  30. Triceps Brachii
    • 3 Heads
    • Extend (straighten) elbow
  31. Pelvic Limb Muscles
    • Locomotion 
    • Muscles of the tarsus, metatarsus, and digits are important for movement 
    • Names give indication of location and function (action)
  32. Gluteal Muscle
    Extend (pull back) the leg (hip joint)
  33. Hamstring Muscles
    • 3 hamstring muscles 
    • extend hip joint 
    • Flex stifle joint
  34. 3 Hamstring Muscles
    • Biceps femoris 
    • Semimembranous
    • Semitendinosis
  35. Quadraceps Femoris
    • Extend stifle joint 
    • Helps bring leg forward
  36. Gastrocnemius Muscle
    • Help propel the body forward
    • Aid in flexing the stifle joint
  37. Muscles of Respiration
    Increase and decrease thoracic cavity to draw air into lungs and push air out of lungs
  38. Inspiration
    Drawing air into lungs
  39. Expiration
    Pushing air out of lungs
  40. Muscles of Inspiration
    • Diaphram 
    • External intercostal
  41. Diaphram
    Flattens, increases size of thoracic cavity, draws air into lungs
  42. External Intercostal
    • Rotate ribs upward and forward
    • Increases thoracic cavity, draws air into lungs
  43. Muscles of Expiration
    • Internal Intercostal 
    • Abdominal Muscles
  44. Internal Intercostal
    • Rotate ribs backwards 
    • Decrease size of thoracic cavity (push air out of lungs)
  45. Abdominal Muscles
    Pushes abdominal organs against diaphram, which pushes
  46. Skeletal Muscle Contraction
    • Dependent on nerve impulse 
    • Neuromuscular Junctions
  47. Neuromuscular Junctions
    • Nerve terminal contains synaptic vessicles 
    • Synaptic vessicles contain ACH (chemical neurotransmitter)
  48. Step 1 of muscular contraction
    • When a nerve impulse is transmitted down a neuron, it causes release of ACH, which quickly binds to receptors on sarcolemma 
    • Starts muscle contraction
  49. Step 2 Of Muscular Contraction
    When ACH binds to receptors, a signal is sent to the sarcoplasmic reticulum (SR) (similar to ER, contains calcium
  50. Step 3 Of Muscular Contraction
    When signal reaches SR, calcium released from SR into sarcoplasm
  51. Step 4 of Muscular Contraction
    Calcium binds to troponin on actin filament (myofilament)
  52. Troponin
    Protein present on actin filament that acts as receptor for calcium
  53. Step 5 of Muscular Contraction
    When calcium binds to troponin, it causes a shift in tropomyosin, which unblocks cross-bridge binding sites
  54. Tropomyosin
    protein present on actin that blocks cross-bridge binding sites (when Ca2+ is low), thereby presenting muscle contraction
  55. Step 6 of Muscle Contraction
    When cross bridge binding sites are open (unblocked by tropomyosin), cross bridges present on myosin can bind to cross bridge binding sites on actin-cross bridge formation
  56. Cross Bridges
    Tiny "levers" on myosin that bind to cross bridge binding sites on actin
  57. Step 7 of Muscle Contraction
    Cross bridges "cocked back" and "pulled forward", drawing actin filaments over myosin filaments
  58. Step 8 of Muscle Contraction
    Results in shortening of the Sarcomere
  59. Step 9 of Muscule Contraction
    Muscle contraction takes place
  60. Muscle Contraction
    • Combined shortening of all sarcomeres in muscle fibers
    • Requires Energy
  61. Step 1 of Muscle Relaxation
    When nerve impulse is removed, ACH is no longer released from synaptic vesicles
  62. Step 2 of Muscle Relaxation
    With no ACH binding to receptors on a sarcolemma, there is no signal to the SR
  63. Step 3 of Muscle Relaxation
    The SR stops releasing Calcium and begins to uptake calcium
  64. Step 4 of Muscle Relaxation
    With no Calcium to bind to troponin, tropomyosin shifts back and covers cross bridge binding sites on actin
  65. Step 5 of Muscle Relaxation
    The cross bridges on myosin are released from cross bridge binding sites on actin
  66. Step 6 of Muscle Relaxation
    • Actin slides back 
    • sarcomere lengthens - muscle relazation
  67. Muscle Relaxation
    • Combined lengthening of sacromeres
    • Requires Energy
  68. ATP
    • Supplies energy for Muscle Contraction and Muscle Relaxation 
    • Produced by the mitochondria found in the sarcoplasm of muscle fiber (cell)
    • Has 3 phosphate groups
  69. Fascicle
    Bundle or cluster of muscle fibers
  70. Myofibril
    Makes up each muscle fiber
  71. Myofilaments
    tiny, contractile filaments that make up each myofibrial
  72. 2 types of proteins that make up myofibril
    • Myosin filaments
    • Actin Filaments
  73. Sarcolemma
    Outer membrane of muscle
  74. Sarcoplasma
    Cytoplasm that surrounds myofibrils make up of connecting sarcomeres
  75. What happens when a phosphate group is split off from ATP
    • ADP is formed and a considerable amount of energy is released
    • Energy powers cross bridge, sliding actin over myosin (contraction)
  76. What is used to convert ADP back to ATP
    Creatine Phosphate
  77. What happens to resulting ATP
    Can be split which releases energy to power uptake of calcium by SR