GEN PHYSIO LAB EX 1-A

• Phases of a simple muscle twitch:

  • Latent period: 0.01 second
  • Begins from the application of the stimulus to the beginning of the response
  • Represents the time necessary for physico-chemical changes for cellular response
  • Represents the time required for the physiological disturbance from stimulation to travel to the whole organ
  • Period of contraction: 0.05 seconds
  • Actual response of the muscle, corresponding to the upstroke of the writing lever
  • Signifies that the muscles have performed work
  • Period of relaxation: 0.06 second
• • Muscle returns to its original resting state
  • Represents the time for resynthesis of products utilized by the muscle during activity so it can respond to succeeding stimuli
• Different types of muscles with respect to duration of contraction:

  • Skeletal muscle:
  • Fastest contraction and shortest duration among the three types
  • Smooth muscle:
  • Longest duration of contraction, ten times longer than skeletal muscle
  • Cardiac muscle:
  • Intermediate duration of contraction between skeletal and smooth muscle
• Different types of the same muscle (skeletal muscle) also differ from each other with respect to muscle contraction