Cards (6)

  • Muscles
    Cells that are elongated to form fibres.
  • Skeletal muscle: Attached to bones, sometimes contracts in response to reflexes, you can control its contraction and relaxation.
    Cardiac Muscle: Found in heart, contracts steadily to make heart rate, you cannot control it.
    Smooth muscle: Found in walls of hollow organs (stomach, bladder), you cannot control it.
  • Sarcomere: span from one z line to the next.
    It's length reduces when the muscles contract which also causes the I band and H zone to be reduced.
  • Actin and myosin are protein filaments found in muscles.
    During contraction, the actin move and overlap the myosin causing the sarcomere to shorten and decrease the overall size of the muscle.
  • Slow-twitch fibres
    • Contract slowly and are less powerful.
    • Used for long periods of times, suited for anaerobic respiration
    • Large store of myoglobin, glycogen
    • Contains numerous mitochondria.
  • Fast-twitch fibres

    • Contract rapidly, very powerful
    • Used for short amounts of times
    • Suited for anaerobic respiration
    • More myosin fibres. (stronger and quicker contractions of muscle.)