Muscle Workings

  1. Myofilament contraction
    myosin head attaches to actin through chemical binding

    myosin head flexes backwards and inwards a few nanometres

    uses ATP to reset the myosin head, reposition it from the actin before each flex

    myosin attaches further along the actin, continues to move the actin further and further
  2. Tropomyosin
    gatekeeper of actin so that myosin cannot bind to actin
  3. Calcium ions
    physically moves tropomyosin so that myosin can bind

    binds to troponin, which is attached to the tropomyosin; the troponin-tropomyosin structure moves, allowing myosin the bind to actin
  4. Sarcoplasmic reticulum
    calcium storehouse
  5. Creatine phosphate
    • 100% natural
    • your body naturally makes this
    • creatine phosphate + adenosine diphosphate (ADP)¬†-> creatine + adenosine triphosphate (ATP)
    • #1, first source of energy for muscles
    • happening in muscle tissue
  6. Creatine supplements
    increases muscle stores of creatine
  7. Aerobic cellular respiration
    • glucose + oxygen + ADP -> carbon dioxide + water +ATP
    • myoglobin - oxygen carrying muscle
  8. shivering
    gain ATP, become warmer
  9. Lactate fermentation
    • a.k.a. anaerobic respiration (not requiring air)
    • buildup of lactate makes sarcoplasm more acidic
    • results in oxygen deficiency, also denaturation of enzymes
    • glucose + ADP -> lactate + ATP
  10. Oxygen debt
    • panting
    • oxygen flushing out lactic acid
  11. Latent period
    time it takes for electricity to go from brain to muscle
  12. Contraction period
    when muscle contracts
  13. Relaxation period
    muscle returning to original length
  14. Slow twitch fibres
    • red bc of myoglobin
    • get energy aerobically
    • lots of mitochondria and blood vessels
    • make a lot of ATP, get a lot of oxygen
  15. Fast twitch fibres
    • energy anaerobically
    • creatine and lactate
    • can fatigue quickly if lactate accumulates
    • rich in glycogen, little mitochondria, blood vessels
    • light in colour because little myoglobin
    • different fibres fire at different voltages
  16. Atrophy
    lose function of muscles
  17. Hypertrophy
    exercise induced increase in muscle mass
  18. Muscular dystrophy
    skeletal muscles degenerate, replaced by fatty tissue that impedes circulation
  19. Botulism
    muscular paralysis caused by ingestion of clostridium botulinum
  20. Tetanus
    muscular paralysis, caused by clostridium tetani
  21. Contracture
    muscle shortening caused by scar tissue
Card Set
Muscle Workings