Physioex Exercise 2 Activity 4
Exercise 2: Skeletal Muscle Physiology: Activity 3: The Effect of Stimulus Frequency on Skeletal Muscle Contraction Lab Report Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. During a single twitch of a skeletal muscle You correctly answered: b. maximal force is never achieved. 2. When a skeletal muscle is repetitively stimulated, twitches can overlap each other and result in a stronger muscle contraction than a stand-alone twitch. This phenomenon is known as You correctly answered: c. wave summation. 3. Wave summation is achieved by You correctly answered: a. increasing the stimulus frequency (the rate of stimulus delivery to the muscle). 4. Wave summation increases the force produced in the muscle. Another way to increase the force produced by a muscle is to You correctly answered: d. increase the number of activated motor units.
02/20/13
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Experiment Results Predict Question: Predict Question 1: As the stimulus frequency increases, what will happen to the muscle force generated with each successive stimulus? Will there be a limit to this response? Your answer : d. As the stimulus frequency increases, the muscle force generated by each successive stimulus will first increase and then decrease as the stimulus frequency becomes very high. Predict Question 2: In order to produce sustained muscle contractions with an active force value of 5.2 grams, do you think you will need to increase the stimulus voltage? Your answer : a. yes Stop & Think Questions: Was there any change in the force generated by the muscle during the second stimulated twitch? You correctly answered: c. Yes, the second twitch generated more muscle force. Is the total muscle force generated by the higher frequency stimulation greater than the force generated in previous stimulations? You correctly answered: a. Yes, it is greater than the previous stimulations. Does the force generated by the muscle change with each additional stimulus? You
02/20/13
page 1
Experiment Results Predict Question: Predict Question 1: As the stimulus frequency increases, what will happen to the muscle force generated with each successive stimulus? Will there be a limit to this response? Your answer : d. As the stimulus frequency increases, the muscle force generated by each successive stimulus will first increase and then decrease as the stimulus frequency becomes very high. Predict Question 2: In order to produce sustained muscle contractions with an active force value of 5.2 grams, do you think you will need to increase the stimulus voltage? Your answer : a. yes Stop & Think Questions: Was there any change in the force generated by the muscle during the second stimulated twitch? You correctly answered: c. Yes, the second twitch generated more muscle force. Is the total muscle force generated by the higher frequency stimulation greater than the force generated in previous stimulations? You correctly answered: a. Yes, it is greater than the previous stimulations. Does the force generated by the muscle change with each additional stimulus? You