Biology Chapter 11

  1. stimulation of a motor neuron
    • 1. acetylchole is released
    • 2. electrical impulse transmitted along T tubules
    • 3. Calcium is released
    • 4. Calcium binds to troponin C
    • 5. Troponin-tropomyosin complex shifts position
    • 6. myosin binding site is exposed
    • 7. myosin heads form cross-bridges with actin. cross bridge cycling occurs.
    • 8. actin filaments are pulled toward center of sacromere
    • 9. calcium is pumped back into sarcoplasmic reticulum
    • 10. muscle relaxation
  2. myosin
    thick filaments
  3. actin
    thin filaments
  4. sarcomeres
    • z disk to z disk
    • z disk = attachment point for sarcomeres
  5. Is energy required for muscle activity?
    • Yes, energy is required.
    • ATP production is important!
  6. contraction
    formation of cross-bridges between thick and thin filaments
  7. isometric
    • same length
    • muscle not allowed to shorten
    • TENSION and FORCE is measured
  8. isotonic
    • same strength (weight)
    • muscle allowed to shorten
    • DISTANCE SHORTENED is measured
  9. motor unit
    somatic motor neuron and all the muscles it stimulates
  10. muscle tension
    force exerted by a contracting muscle
  11. all-or-none principle
    mucle cells always contract completely each time they are stimulated by their motor neuron, and they do not contract at all if they are not stimulated by a motor neuron
  12. muscle tone
    intermediate level of force
  13. summation
    accumulation of effects, especially those of muscular (or neural) activity
  14. tetanus
    sustained maximal muscle contraction resulting from high frequency stimulation
  15. slow twitch
    • slow, steady contractions; muscles used for posture
    • do not fatigue easily
    • use aerobic pathway to generate ATP
    • many mitochondria to produce ATP
    • well supplied with blood bringing needed oxygen
    • high oxygen store (myoglobin) within the muscle
    • myoglobin and numerous blood vessels give muscle reddish color; "red" meat
  16. fast twitch
    • quick, powerful bursts of energy; muscles used by sprinters
    • fatigue easily
    • use anaerobic pathway (glycolysis) to generate ATP
    • few mitochondria to produce ATP
    • not supplied with much blood
    • low myoglobin concentrated with muscle cells
    • sometimes referred to as "white" meat
  17. strength training
    • resistance training
    • short, intence
    • builds more fast-twitch myofibrils
  18. aerobic training
    • builds endurance
    • increases blood supply to muscle cells
    • reach target heart rate at least 20 minutes, three times a week
  19. skeletal muscle
    voluntary (through somatic nervous system)
  20. Activation of cardiac and smooth muscles. Voluntary or Involuntary?
    Involuntary
  21. Muscular Dystrophy
    group of inherited muscle-destroying diseases. Duchenne's muscular dystrophy is due to lack of the protein dystrophin in the muscle cell.
Author
samigrim
ID
139149
Card Set
Biology Chapter 11
Description
Chapter 11
Updated