26-5-2021 PhysioEx Exercise 2 Activity 4
PhysioEx Lab Report
Exercise 2: Skeletal Muscle Physiology
Activity 4: Tetanus in Isolated Skeletal Muscle
Name:
Date
Session ID
Pre-lab Quiz Results
You scored 100% by answering 3 out of 3 questions correctly.
1 Stimulus frequency refers to
You correctly answered: 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: 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: maximal tetanic
tension.
Experiment Results
Predict Question
1 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: As the stimulus frequency increases, the muscle tension generated by each successive
stimulus will increase. There will be a limit to this increase.
Stop & Think Questions
1 What begins to happen at around 80 msec?
You correctly answered: unfused tetanus develops.
2 How does the trace at 130 stimuli/sec compare with the trace at 50 stimuli/sec?
You correctly answered: Fused tetanus develops at this greater stimulus frequency.
3 How do the traces with 146-150 stimuli per second compare with the trace at 130 stimuli per second?
You correctly answered: Maximal tetanic tension develops with these very high stimulation
frequencies.
https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act4/ 1/6
, 26-5-2021 PhysioEx Exercise 2 Activity 4
Experiment Data
Voltage (v) Length (mm) Stimuli/sec Act. Force Pass. Force Total Force
8.5 75 50 5.12 0 5.12
8.5 75 130 5.88 0 5.88
8.5 75 140 5.91 0 5.91
8.5 75 142 5.92 0 5.92
8.5 75 144 5.94 0 5.94
8.5 75 146 5.95 0 5.95
8.5 75 148 5.95 0 5.95
8.5 75 150 5.95 0 5.95
https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act4/ 2/6
PhysioEx Lab Report
Exercise 2: Skeletal Muscle Physiology
Activity 4: Tetanus in Isolated Skeletal Muscle
Name:
Date
Session ID
Pre-lab Quiz Results
You scored 100% by answering 3 out of 3 questions correctly.
1 Stimulus frequency refers to
You correctly answered: 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: 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: maximal tetanic
tension.
Experiment Results
Predict Question
1 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: As the stimulus frequency increases, the muscle tension generated by each successive
stimulus will increase. There will be a limit to this increase.
Stop & Think Questions
1 What begins to happen at around 80 msec?
You correctly answered: unfused tetanus develops.
2 How does the trace at 130 stimuli/sec compare with the trace at 50 stimuli/sec?
You correctly answered: Fused tetanus develops at this greater stimulus frequency.
3 How do the traces with 146-150 stimuli per second compare with the trace at 130 stimuli per second?
You correctly answered: Maximal tetanic tension develops with these very high stimulation
frequencies.
https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act4/ 1/6
, 26-5-2021 PhysioEx Exercise 2 Activity 4
Experiment Data
Voltage (v) Length (mm) Stimuli/sec Act. Force Pass. Force Total Force
8.5 75 50 5.12 0 5.12
8.5 75 130 5.88 0 5.88
8.5 75 140 5.91 0 5.91
8.5 75 142 5.92 0 5.92
8.5 75 144 5.94 0 5.94
8.5 75 146 5.95 0 5.95
8.5 75 148 5.95 0 5.95
8.5 75 150 5.95 0 5.95
https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act4/ 2/6
