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Experiment Results Predict Question: Predict Question: As the resting length of the muscle is changed, what will happen to the amount of total force the muscle generates during the stimulated twitch? Your answer : d. An increase in muscle length will decrease the total force. Stop & Think Questions: Note the dip in total force at a muscle length of 90 mm. Why does this occur? You correctly answered: d. At this muscle length, active force has decreased in value and passive force has not yet increased to a significant value. Experiment Data: Voltage 8.5 8.5 8.5 8.5 8.5 8.5 8.5 8.5 8.5 Length 75 70 65 60 55 50 80 90 100 Active Force 1.82 1.75 1.55 1.21 0.73 0.11 1.75 1.21 0.11 Passive Force 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.25 1.75 Total Force 1.82 1.75 1.55 1.21 0.73 0.11 1.77 1.46 1.86
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Post-lab Quiz Results You scored 60% by answering 3 out of 5 questions correctly. 1. When a skeletal muscle is stimulated and generates force but remains at a fixed length You correctly answered: d. the muscle is contracting isometrically. 2. Which protein is mostly responsible for the development of passive force in a muscle? You correctly answered: d. titin 3. In skeletal muscle, active force stimulated through a range of muscle lengths Your answer: c. will always be the dominant value contributing to the total force of the muscle. Correct answer: b. will utilize ATP hydrolysis to drive the cross bridge cycle. 4. Which if the following is not depicted in a typical skeletal muscle isometric length-tension curve? You correctly answered: a. time 5. Maximal active tension will be produced in a skeletal muscle fiber when Your