skeletal muscle physiology

  1. sarcoplasmic reticulum is an organelle found only in
    muscle cells
  2. muscle cells are multi-nucleated and are called
    muscle fibers
  3. calcium ions bind to this to lead to muscle contraction
  4. troponin binds to this to lead to muscle contraction
    calcium ions
  5. calcium ions are released into the cytosol from this organelle
    sarcoplasmic reticulum
  6. muscle fibers contain myofibrils composed of arrays of
  7. myofibrils are
    cylindrical bundles within the muscle cells (within the muscle fibers)
  8. the filaments within myofibrils within muscle fibers (muscle cells) are arranged this way
    in a repeating pattern
  9. one repeat of the pattern of the filaments within the myofibrils is called the
  10. thick filaments are made of
  11. thin filaments are made of 3 proteins that regulate contraction, called
    actin, troponin and tropomyosin
  12. myosin is a
    motor protein
  13. actin is a
    cytoskeletal protein
  14. the wide, dark "A" band is composed of the
    thick filaments
  15. sizewise, the thin filaments are
    half the diameter of the thick filaments
  16. each muscle fiber behaves as
    a single unit
  17. each muscle fiber is multi-
  18. each muscle fiber contains these
  19. the banding pattern seen in striated muscle are actually the repeating units of
  20. a myosin thick filament has a heavychain tail and this many heads
  21. troponin is a complex of 3 proteins:
    troponin I, troponin T, troponin C
  22. troponin I
  23. troponin T
  24. troponin C
  25. a thick filament has 2
    a thick filament has 2 heads
  26. a thin filament is made of the
    3 troponins (composed as "troponin") wound around with actin, and tropomyosin
  27. tropomyosin is
    a filamentous protein that runs along the groove of each twisted actin filament
  28. myosin makes up these filaments
  29. actin makes up these filaments
    thin (along with tropomyosin and the 3-part troponin)
  30. this textbook arrangement of the thin filament is present when a muscle is
    at rest
  31. in order to contract, this must get out of the way of the actin
  32. once tropomyosin gets out of actin's way,
    actin (thin) and myosin (thick) can interact. actin has sites for myosin to bind
  33. when the muscle is at rest, the myosin-binding sites on the actin are covered by
    tropomyosin, so that actin and myosin cannot interact
  34. in order to contract, actin (thin) and myosin (thick) must
Card Set
skeletal muscle physiology
moreau lectures, brooker book, costanzo