Name: kelompok 5

Exercise 2: Skeletal Muscle Physiology: Activity 6: The Skeletal Muscle Length-Tension Relationship Lab Report

Pre-lab Quiz ResultsYou scored 80% by answering 4 out of 5 questions correctly.

1. During an isometric contractionYou correctly answered: d. the skeletal muscle is generating force, but it remains at a fixed length.

2. The force that results from muscles being stretched isYou correctly answered: a. passive force.

3. Active forceYour answer : c. equals total force.Correct answer: b. is determined by the amount of myosin bound to actin.

4. When you generate the isometric length-tension curve, which of the following forces will not be indicated on yourscreen?You correctly answered: c. tetanic force

5. Passive force in skeletal muscle is largely caused byYou correctly answered: c. the protein titin.

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Experiment ResultsPredict Question:Predict Question: As the resting length of the muscle is changed, what will happen to the amount of total force the musclegenerates during the stimulated twitch?You did not answer this question.

Stop & Think Questions:Note the dip in total force at a muscle length of 90 mm as compared to the total force at a muscle length of 80 and 100 mm. Why does this occur?You did not answer this question.Correct answer: d. At this muscle length, active force has decreased in value and passive force has not yet increased to asignificant value.

Experiment Data:

Voltage Length Active Force Passive Force Total Force8.5 75 1.82 0.02 1.848.5 70 1.75 0.0 1.758.5 65 1.55 0.0 1.558.5 60 1.21 0.0 1.218.5 55 0.73 0.0 0.738.5 50 0.11 0.0 0.118.5 80 1.75 0.02 1.778.5 75 1.82 0.0 1.828.5 85 1.55 0.08 1.638.5 95 0.73 0.68 1.418.5 100 0.11 1.75 1.86

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Post-lab Quiz ResultsYou scored 80% by answering 4 out of 5 questions correctly.

1. When a skeletal muscle is stimulated and generates force but remains at a fixed lengthYou 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 lengthsYou correctly answered: b. will utilize ATP hydrolysis to drive the cross bridge cycle.

4. Which of 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 whenYour answer: d. the fiber is at any length because tension is not dependent on muscle length.Correct answer: a. the fiber is at its resting length.

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Review Sheet Results1. What happens to the amount of total force the muscle generates during the stimulated twitch? How well did the resultscompare with your prediction?Your answer:jika otot diberikan stimulasi maka gaya total yang diberikan akan sampai optimum

2. What is the key variable in an isometric contraction of a skeletal muscle?Your answer:isometrik akan terjadi dengan bantuan tendon , kerika tangan mendorong benda dan panjang otot yang maksimal . otottetap memendek karena fase kontraksi dengan bantuan tendon akan terjadi elastisitas otot.

3. Based on the unique arrangement of myosin and actin in skeletal muscle sarcomeres, explain why active force varieswith changes in the muscle's resting length.Your answer:setelah otot beristirahat, otot memerlukan waktu yang tepat untuk memulai kontraksinya kembali

4. What skeletal muscle lengths generated passive force? (Provide a range.)Your answer:panjang otot yang maksimal dan yang hanya sesuai panjang optimum

5. If you were curling a 7-kg dumbbell, when would your bicep muscles be contracting isometrically?Your answer:isometrik otot yang akan terjadi , bila terjadi pelurusan tangan