Muscle Contraction and Wave Summation
Exercise 2: Skeletal Muscle Physiology: Activity 3: The Effect of Stimulus Frequency on Skeletal Muscle Contraction Lab
Report
Pre-lab Quiz Results
You scored 25% by answering 1 out of 4 questions correctly.
1. During a single twitch of a skeletal muscle
Your answer : a. calcium is not released from the sarcoplasmic reticulum.
Correct answer: 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
Your answer : d. allowing the muscle to completely relax between stimuli.
Correct answer: 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
Your answer : a. slow action potential propagation down the motor neurons that innervate the muscle.
Correct answer: d. increase the number of activated motor units.
010/03/13
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 : b. As the stimulus frequency increases, the muscle force generated by each successive stimulus will increase. There will be a limit to this increase.
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
Report
Pre-lab Quiz Results
You scored 25% by answering 1 out of 4 questions correctly.
1. During a single twitch of a skeletal muscle
Your answer : a. calcium is not released from the sarcoplasmic reticulum.
Correct answer: 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
Your answer : d. allowing the muscle to completely relax between stimuli.
Correct answer: 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
Your answer : a. slow action potential propagation down the motor neurons that innervate the muscle.
Correct answer: d. increase the number of activated motor units.
010/03/13
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 : b. As the stimulus frequency increases, the muscle force generated by each successive stimulus will increase. There will be a limit to this increase.
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