muscles & filaments

  1. portion of the myofibril
  2. runs from z line to z line
  3. dark band that has thick filaments and thin filaments
    A band
  4. portion of A band that contain only thick filament
    H zone
  5. during muscle contraction what happens to the h zone
    disappear because the thin filaments invade the h zone
  6. central portion of a thick filament which is connected by proteins
    m line
  7. contains z line and thin filaments
    I band
  8. zig-zag shaped line is a membrand where the thin filaments are attached
    Z line
  9. these are long proteins made either of action or myosin
  10. possess heads which are crucial for muscle contraction
    thick filaments
  11. covers active site on actin and prevents actin and myosin heads from interacting.
    tropomyosin (protein)
  12. tropomyosin is connected to
  13. for muscle contraction to occur:
    troponin-tropomyosin must change and expose active sites on actin.
  14. What binds troponin and allows change in shape so that myosin heads can attach to the thin filaments.
  15. these heads are made of proteins which attach to a particular portion of the thin filaments during muscle contraction
    myosin head
  16. When the myosin heads attach to the thin filaments they are then called
    cross bridge
  17. anchored to the z line
    thin filaments
  18. what is the role of the myosin heads
    attach to the thin filaments, pull them, release & repeat.
  19. organelle is wrapped around the myofibril like a lacey sleeve
    sarcoplasmic reticulum
  20. for muscle contraction to begin
    calcium ions are released from the SR into the sacroplasm.
  21. What reabsorbs calium ions after muscle contraction to help the muscle relax
    Sacroplasmic reticulum
  22. plasma membrane of the muscle cell
  23. long filamentous organelle found in muscle cells; band appearance
  24. in order for the entire muscle cell to contract at the same time-
    transverse (T) extend into the cell at right angles to the cell's surface
  25. at the end of each muscle, the collagen fibers of the endomysium and perimysium come together to for either a ______ or________
    tendon or aponeuroses
  26. both connect skeletal muscles to bone
    tendon and aponeroses
  27. connect muscle to muscle
  28. this layer is connected to the fascia
  29. contains collagen and elastic fibers, nerves and blood vessels
  30. (cytoplasm) of the muscle cell
  31. muscle's ability to react to a stimulus
  32. muscle shortens upon stimulation
  33. muscle returns to normal length after stretching.
Card Set
muscles & filaments
muscles & filaments