A&P week 1

  1. myofilaments consist of which main proteins
    • myosin: Thick or
    • actin: thin
  2. multiple ___ are organized into a muscle fiber
  3. multiple fibers are organized into a ___
  4. multiple fascicles are organized into a ___
  5. Each tropomyosin molecule has a calcium-binding protein called ____ bound to it.
  6. explain excitation process that leads to excitation-contraction coupling and contraction.
    1) a nerve signal arrives at the synaptic knob and opens voltage-gated Ca channels.  Ca ions enter the knob and stimulate the release of Acetocholine (ACH).

    2) Ach diffuses across the synaptic cleft and binds to receptors in the sarcolemma.

    3) Receptors are ligand-gated. 2 ACh molecules need to bind  to open a receptor.

    4) Na flows in, K flows out until the voltage jumps from RMP -90 to +75mV, which created the end-plate potential.

    5) Ion channels in the sarcolemma open in response to the end-plate potential, allowing Na in and K out of the sarcolemma.
  7. Explain the steps of excitation-contraction coupling:
    1) a wave of action potential spreads from the motor end plate in all directions to the t-tubules, which are linked to Ca channels in the terminal cisternea of the sarcoplasmic reticulum.

    2) Ca channels open in the sarcoplasmic reticulum (SR) and flow down the concentration gradient to the cytosol.

    3) Ca binds to the troponin in the thin filament (actin).  The troponin-tropomyosin complex changes shape, exposing the active sites on the actin filaments.  

    4) ATP initiates contraction by binding to myosin head. Myosin ATPase hydrolyzes aTP into ADP and phosphate, releasing the energy needed to cock it's head forming a cross bridge.

    5) Myosin releases the ADP and P, and flexes into a bent position, tugging (power stroke) the thin filament along. 

    6) APT binds to the myosin, breaking the cross bridge, and repeating the process.
  8. abducotrs
    away from the midline.
  9. adductors
    toward the midline.
  10. ______ are the filaments of myofibrils
  11. the agonist or antagonist apposes the prime mover
  12. another name for prime mover is
    agonist. Initiates movement
  13. the ____ helps the agonist
  14. adbuctors move away or toward the midline
    away from the midline.
  15. adductors move away or toward the midline
  16. ____ is a functional unit of a muscle fiber
    sarcomere (from z-disc to z-disc).
  17. 2 muscle fiber typles
    • type 1: oxidative (slow) (endurance)
    • type 2: glycolytic (fast). IIA & IIB. (power athletes)
  18. protein that functions as a muscle spring
  19. synapse between a nerve fiber and muscle fiber: also called a motor end plate
    neuromuscular junction
  20. motion that moves the leg back
  21. motion that moves leg forward
  22. occurring on the same side
  23. occurring on the opposite side
  24. moving medial foot up
  25. moving later part of foot up
  26. moving toes up
  27. moving toes down
  28. 4 strategies to regain balance
    • 1) ankle strategy
    • 2) hip strategy
    • 3) step strategy
    • 4( suspensory strategy.
  29. Image Upload 1
    ankle strategy, forward sway.
  30. Image Upload 2
    ankle strategy, backward sway.
  31. Image Upload 3
    hip strategy, forward sway
  32. Image Upload 4
    hip strategy, backward sway.
  33. process of walking is called the
    gait cycle.
  34. Name each graph of joint angle during gait
    Image Upload 5
    Hip, knee, ankle
  35. list steps in gait cycle
    • 1) heel strike
    • 2) foot flat
    • 3) midstance
    • 4) heel off
    • 5) toe off
Card Set
A&P week 1