Ch. 11 c Twitch/contractions (lecture)

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Ch. 11 c Twitch/contractions (lecture)
2014-03-30 22:43:57
cgcc boerboom

Twitch contractions questions
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  1. What is a twitch?
    A quick cycle of contraction and relaxation
  2. What contraction involves a change in muscle tension, but not muscle length?
    Isometric contraction (iso=same metric=length). ex. holding a book in your hand, then adding another book but not moving it.
  3. What contraction involves a change in muscle length, but not tension (weight on muscle)?
    Isotonic contraction (iso=same tonic=tension)
  4. What are the two forms/directions of isotonic contractions?
    • Concentric (muscle shortens) ex. arm curls
    • Eccentric (muscle extends) ex. lowering arms
  5. Sources of ATP: What is Aerobic respiration?
    With enough oxygen; glucose is converted into ATP
  6. Sources of ATP: What is Anaerobic respiration?
    • Without enough oxygen, backup systems are used: Creatine phosphate contributes to conversion of ADP to ATP. Also oxygen is taken from myoglobin. These need to be replenished after exercise
    • Stored ATP is also a source of ATP
  7. What are some reasons for muscle fatigue?
    • ATP synthesis slows, ability of sodium-potassium pump to regulate RMP drops
    • Lactic acid lowers pH of sarcoplasm
  8. What is maximum oxygen uptake?
    The peak/plateau of a person’s oxygen consumption
  9. What are type one slow-twitch fibers?
    • Fatigue resistant fibers, darker color
    • Relies on aerobic respiration and has a long twitch
    • Ex. postural muscles of back
  10. What are type two fast-twitch fibers?
    • Paler appearance due to lack of capillaries and other nutrient-giving bodies
    • Uses glycogen for energy and rapid ATP use.
    • Ex. Calf muscles (though is a mix with slow-twitch)
  11. What is resistance training?
    • Muscle contraction against a load
    • Muscles synthesize more myofilaments, making muscles bigger
  12. What is endurance training?
    Improves fatigue resistant muscles, makes slow twitch fibers make more mitochondria which means more ATP