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Physiology
Skeletal Muscle Mechanics - Test 4
Question | Answer |
---|---|
What is skeletal muscle mechanics? | How skeletal muscle operates to perform a function |
What is a single muscle twitch? | A skeletal muscle contraction resulting from a single action potential |
True or False, the electrical event precedes the mechanical event? | True |
Why is single twitch submaximal? | The sarcoplasmic reticulum Ca++ATPase lowers the Ca++ concentrations before the skeletal muscle can develop its maximum tension |
What is a multiple twitch? | It is when skeletal muscle responds to several multiple action potentials delivered at a high frequency which increases the force of contraction up to the maximum tension. |
What are the two methods of producing a graded response that allows to produce just the force needed to lift a specific load? | 1. Frequency 2. Recruitment |
What is temporal Summation? | A series of action potentials generated at a high enough frequency to increase the tension in a skeletal muscle fiber beyond that produced by a single action potential |
What is tetany? | Maximal skeletal muscle contraction produced by a series of hihg frequency action potentials |
What are the 2 types of fatigue? | 1. Nerve Fatigue 2. Skeletal fatigue |
What causes nerve fatigue? | The depletion of neurotransmitter |
What causes muscle fatigue? | Depletion of glycogen storage |
True or false, the more sarcomeres a skeletal muscle has in parallel, the stronger the fiber becomes? | True |
True or false, the more sarcomeres a skeletal muscle has in series, the faster its velocity of contraction becomes? | True |
What is a motor unit? | The alpha motor neuron and all aof the skeletal muscle fibers it innervates. |
How many muscle fibers does a motor unit consist of? | As many as One fiber to several Thousand. |
Once max tension is acheived in a muscle fiber, can an increase in nerve stimulation continue to increase the force of contraction? | No. |
The graded response that activates the smallest motor units first, then larger and larger units are added until the load is lifted, is refered to what process? | Recruitment |
True or False, skeletal muscle contraction involves both an active tension and a passive tension? | True |
What is the active tension curve displaying? | The shortening of the sarcomere |
What is the Total Tension curve? | The addition of the passive tension curve plus the active tension curve |
In the active tension curve where does resting sarcomere length occur? | At the peak |
In the passive tension curve where is the resting sarcomere length displayed? | At the very beginning |
How many different types of muscle fibers are there? | 3: Fast Glycolytic (White), Fast Oxidative Glycolytic (Fast Red), and Slow Oxidative (Red) |
True or False, White muscle fibers are used for endurance? | False, White fibers contibute the power or strength |
What is the most abundant skeletal muscle fibers in humans? | Fast Oxidative Glycolytic (Fast Red) |
What type of muscle fibers predominately express the enzymes involved in glycolysis? | Fast Glycolytic or White |
What type of muscle fibers evenly express the enzymes involved in glycolysis and the Keb's Cycle? | Fast Oxidative Glycolytic or Fast Red Fibers |
What type of muscle fibers predominately express the enzymes involved in the Kreb's Cycle? | Slow Oxidative or Slow Red |
True or Fasle, Every muscle group contains all three fiber types? | True |
Which type of muscle fiber can be expressed as another type depending upon the persons activities? | Fast Oxidative Glycolytic or Fast Red |