Physio Ex Exercise 2 Activity 6 PDF

Preview

Summary

Download Physio Ex Exercise 2 Activity 6 PDF

Description

10/9/2020

PhysioEx Exercise 2 Activity 6

PhysioEx Lab Report Exercise 2: Skeletal Muscle Physiology Activity 6: The Skeletal Muscle Length-Tension Relationship Name: Dyreante Notto Date: 9 October 2020 Session ID: session-9c8986e4-4cf2-458b-271f-90223e65d60a

Pre-lab Quiz Results You scored 100% by answering 5 out of 5 questions correctly. 1 During an isometric contraction You correctly answered: the skeletal muscle is generating force, but it remains at a fixed length. 2 The force that results from muscles being stretched is You correctly answered: passive force. 3 Active force You correctly answered: 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 your screen? You correctly answered: tetanic force. 5 Passive force in skeletal muscle is largely caused by You correctly answered: the protein titin.

Experiment Results Predict Question https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

i 1/11

10/9/2020

PhysioEx Exercise 2 Activity 6

1 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: An increase in muscle length will increase total force. Stop & Think Question 1 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 correctly answered: At this muscle length, active force has decreased in value and passive force has not yet increased to a significant value. Experiment Data Voltage (v)

Length (mm) Active Force Passive Force Total Force

8.5

75

1.82

0

1.82

8.5

70

1.75

0

1.75

8.5

65

1.55

0

1.55

8.5

60

1.21

0

1.21

8.5

55

0.73

0

0.73

8.5

50

0.11

0

0.11

8.5

80

1.75

0.02

1.77

8.5

90

1.21

0.25

1.46

8.5

100

0.11

1.75

1.86

Muscle Length = 75 mm Active Force = 1.82 Passive Force = 0 Total Force = 1.82

i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

2/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Active Force Passive Force Total Force

Muscle Length = 75 mm Active Force = 1.82 Passive Force = 0 Total Force = 1.82

Muscle Length = 70 mm Active Force = 1.75 Passive Force = 0 Total Force = 1.75

Active Force Passive Force Total Force

Muscle Length = 70 mm Active Force = 1.75 i

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

3/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Passive Force = 0 Total Force = 1.75

Muscle Length = 65 mm Active Force = 1.55 Passive Force = 0 Total Force = 1.55

Active Force Passive Force Total Force

Muscle Length = 65 mm Active Force = 1.55 Passive Force = 0 Total Force = 1.55

Muscle Length = 60 mm Active Force = 1.21 i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

4/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Passive Force = 0 Total Force = 1.21

Active Force Passive Force Total Force

Muscle Length = 60 mm Active Force = 1.21 Passive Force = 0 Total Force = 1.21

Muscle Length = 55 mm Active Force = 0.73 Passive Force = 0 Total Force = 0.73

Active Force Passive Force Total Force

Muscle Length = 55 mm Active Force = 0.73 i

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

5/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Passive Force = 0 Total Force = 0.73

Muscle Length = 50 mm Active Force = 0.11 Passive Force = 0 Total Force = 0.11

Active Force Passive Force Total Force

Muscle Length = 50 mm Active Force = 0.11 Passive Force = 0 Total Force = 0.11

Muscle Length = 80 mm Active Force = 1.75 i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

6/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Passive Force = 0.02 Total Force = 1.77

Active Force Passive Force Total Force

Muscle Length = 80 mm Active Force = 1.75 Passive Force = 0.02 Total Force = 1.77

Muscle Length = 90 mm Active Force = 1.21 Passive Force = 0.25 Total Force = 1.46

Active Force Passive Force Total Force

Muscle Length = 90 mm Active Force = 1.21 i

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

7/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Passive Force = 0.25 Total Force = 1.46

Muscle Length = 100 mm Active Force = 0.11 Passive Force = 1.75 Total Force = 1.86

Active Force Passive Force Total Force

Muscle Length = 100 mm Active Force = 0.11 Passive Force = 1.75 Total Force = 1.86

i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

8/11

10/9/2020

PhysioEx Exercise 2 Activity 6

Post-lab Quiz Results You scored 100% by answering 5 out of 5 questions correctly. 1 When a skeletal muscle is stimulated and generates force but remains at a fixed length You correctly answered: the muscle is contracting isometrically. i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

9/11

10/9/2020

PhysioEx Exercise 2 Activity 6

2 Which protein is mostly responsible for the development of passive force in a muscle? You correctly answered: titin. 3 In skeletal muscle, active force stimulated through a range of muscle lengths You correctly answered: 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: time. 5 Maximal active tension will be produced in a skeletal muscle fiber when You correctly answered: the fiber is at its resting length.

Review Sheet Results 1 What happens to the amount of total force the muscle generates during the stimulated twitch? How well did the results compare with your prediction? Your answer: As the muscle length decreases, the total force decreases, so my prediction was incorrect and I experienced this during the experiment. 2 What is the key variable in an isometric contraction of a skeletal muscle? Your answer: The muscle is at a fixed length, the length does not affect the total force. 3 Based on the unique arrangement of myosin and actin in skeletal muscle sarcomeres, explain why active force varies with changes in the muscle's https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

i 10/11

10/9/2020

PhysioEx Exercise 2 Activity 6

resting length. Your answer: The longer the resting length is, the more time it allows for all the myosin bridges to go back to their original position. 4 What skeletal muscle lengths generated passive force? (Provide a range.) Your answer: 80-100mm. 5 If you were curling a 7-kg dumbbell, when would your bicep muscles be contracting isometrically? Your answer: when you lift the dumbbell up your bicep muscles will be contracting isometrically.

i https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex2/act6/

11/11...