Physio Ex Exercise 2 Activity 4 PDF

Preview

Summary

Pearson PhysioEx Lab ...

Description

PhysioEx Lab Report Exercise 2: Skeletal Muscle Physiology Activity 4: Tetanus in Isolated Skeletal Muscle Name: Kaley Faucher Date: 15 September 2020 Session ID: session-747fe00f-1c6c-7f46-9617-afd467bc51f0

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. 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

150

5.95

0

5.95

Stimuli/sec = 50 at 8.5 V

Stimuli/sec = 130 at 8.5 V

Stimuli/sec = 140 at 8.5 V

Stimuli/sec = 150 at 8.5 V

Post-lab Quiz Results You scored 100% by answering 3 out of 3 questions correctly. 1 The term tetanus refers to You correctly answered: sustained muscle tension due to very frequent stimuli. 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 between different values for an 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.

Review Sheet Results 1 Describe how increasing the stimulus frequency affected the force developed by the isolated whole skeletal muscle in this activity. How well did the results compare with your prediction? Your answer: My predication was correct. 2 Indicate what type of force was developed by the isolated skeletal muscle in this activity at the following stimulus frequencies: at 50 stimuli/sec, at 140 stimuli/sec, and above 146 stimuli/sec. Your answer: 50 stimuli/sec : unused tetanus 140 stimuli/sec : complete fused tetanus 146+ stimulus/sec : maximal tetanic tension. 3 Beyond what stimulus frequency is there no further increase in the peak force? What is the muscle tension called at this frequency? Your answer: maximal tetanic tension was achieved at 150 stimuli/sec....