Physioex 9.0 Exercise 2
Exercise 2: Skeletal Muscle Physiology: Activity 4: Tetanus in Isolated Skeletal Muscle Lab Report Pre-lab Quiz Results You scored 100% by answering 3 out of 3 questions correctly. 1. Stimulus frequency refers to You correctly answered: b. the rate that stimulating voltage pulses are applied to an isolated whole skeletal muscle. 2. Which of the following distinguishes a state of unfused tetanus from a state of complete (fused) tetanus? You correctly answered: d. Muscle tension increases and decreases during a state of unfused tetanus. 3. When the stimulus frequency reaches a value beyond which no further increases in force are generated by the muscle, the muscle has reached its You correctly answered: a. maximal tetanic tension.
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Experiment Results Predict Question: Predict Question: As the stimulus frequency increases further, what will happen to the muscle tension and twitch appearance with each successive stimulus? Will there be a limit to this response? Your answer : a. As the stimulus frequency increases, the muscle tension generated by each successive stimulus will increase. There will be no limit to this increase. Stop & Think Questions: What begins to happen at around 80 msec? You correctly answered: c. unfused tetanus develops How does the trace at 130 stimuli/sec compare with the trace at 50 stimuli/sec? You correctly answered: b. Fused tetanus develops at this greater stimulus frequency. How do the traces with 146–150 stimuli per second compare with the trace at 130 stimuli per second? You correctly answered: d. Maximal tetanic tension develops with these very high stimulation frequencies. Experiment Data: Voltage 8.5 8.5 8.5 8.5 8.5 8.5 8.5 8.5 Length 75 75 75 75 75 75 75 75 Stimuli/sec 50 130 140 142 144 146 148 150 Active Force 5.12 5.88 5.91 5.94 5.94 5.95 5.95 5.95 Passive Force 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total Force 5.12 5.88 5.91 5.94 5.94 5.95 5.95 5.95
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Experiment Results Predict Question: Predict Question: As the stimulus frequency increases further, what will happen to the muscle tension and twitch appearance with each successive stimulus? Will there be a limit to this response? Your answer : a. As the stimulus frequency increases, the muscle tension generated by each successive stimulus will increase. There will be no limit to this increase. Stop & Think Questions: What begins to happen at around 80 msec? You correctly answered: c. unfused tetanus develops How does the trace at 130 stimuli/sec compare with the trace at 50 stimuli/sec? You correctly answered: b. Fused tetanus develops at this greater stimulus frequency. How do the traces with 146–150 stimuli per second compare with the trace at 130 stimuli per second? You correctly answered: d. Maximal tetanic tension develops with these very high stimulation frequencies. Experiment Data: Voltage 8.5 8.5 8.5 8.5 8.5 8.5 8.5 8.5 Length 75 75 75 75 75 75 75 75 Stimuli/sec 50 130 140 142 144 146 148 150 Active Force 5.12 5.88 5.91 5.94 5.94 5.95 5.95 5.95 Passive Force 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total Force 5.12 5.88 5.91 5.94 5.94 5.95 5.95 5.95
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