Question 1

Which of the following statements is true regarding cross-bridges?

Accepted Answer

A)  A cross-bridge is the basic unit of active muscle tension. 
B)  A cross-bridge is formed when head groups on the actin myofilament bind with tropomyosin on the myosin filament. 
C)  Cross-bridges do not occur in lengthening contractions. 
D)  A release of sodium is necessary to reveal the binding site on the actin. 
A)  A cross-bridge is the basic unit of active muscle tension. 
B)  A cross-bridge is formed when head groups on the actin myofilament bind with tropomyosin on the myosin filament. 
C)  Cross-bridges do not occur in lengthening contractions. 
D)  A release of sodium is necessary to reveal the binding site on the actin. A

Question 2

Contrast active and passive insufficiency.Give examples of each using the same muscle.

Accepted Answer

Active insufficiency occurs when a muscle is trying to shorten but generates inadequate tension to perform its desired function.That is,when a muscle is actively insufficient,it is either fully shortened or fully lengthened,and actively attempting to shorten further.Passive insufficiency occurs when a passive muscle is being stretched over the joint(s)it crosses and reaches the limits of its extensibility.When this occurs,the muscle prevents further movement.The biceps brachii is passively insufficient when both the elbow and the shoulder are fully extended and further extension is being attempted by some other force.The restriction in further movement is due to the tension in the passive muscle.

Question 3

You are passively stretching the hip flexors of a patient in the position of prone hip extension and knee flexion.You later note that the patient demonstrates greater hip extension passive range of motion (PROM)when you allow the knee to be straight during the stretching procedure.The reason for the improved hip extension PROM may best be explained by ____________________.

Accepted Answer

A)  elimination of active insufficiency that occurred during the original position 
B)  elimination of passive insufficiency that occurred during the original position 
C)  elimination of both active and passive insufficiency that occurred during the original position 
D)  activation of passive insufficiency that occurred in the second position 
A)  elimination of active insufficiency that occurred during the original position 
B)  elimination of passive insufficiency that occurred during the original position 
C)  elimination of both active and passive insufficiency that occurred during the original position 
D)  activation of passive insufficiency that occurred in the second position B

Question 4

When the body segments act in a closed kinematic chain,are muscles most commonly acting in normal or reverse action?

Accepted Answer

Reverse action.This is when the proximal

Question 5

The elbow flexors will exert the greatest amount of torque/tension for which type of muscle contraction?

Accepted Answer

A)  Isometric 
B)  Eccentric 
C)  Concentric 
D)  Synergistic 
A)  Isometric 
B)  Eccentric 
C)  Concentric 
D)  Synergistic

Question 6

Your patient holds a weight in his right hand.Consider only the muscle activity of the elbow flexors.What type of muscle contraction would occur if TM = 400 N,and TL = 500 N,and motion is in the direction of elbow extension? (TM = torque of muscle; TL = torque of load)

Accepted Answer

A)  Isometric 
B)  Concentric 
C)  Eccentric 
D)  Synergistic 
A)  Isometric 
B)  Concentric 
C)  Eccentric 
D)  Synergistic

Question 7

Which of the following statements best describes the length-tension relationship of a muscle?

Accepted Answer

A)  The total amount of tension a muscle can develop is related only to the muscle's active tension. 
B)  During active concentric contraction,maximal tension is developed in the muscle's midrange. 
C)  During active shortening,no tension is present after all cross-bridges have formed and the myofilaments are overlapping. 
D)  All of the above answers are correct. 
A)  The total amount of tension a muscle can develop is related only to the muscle's active tension. 
B)  During active concentric contraction,maximal tension is developed in the muscle's midrange. 
C)  During active shortening,no tension is present after all cross-bridges have formed and the myofilaments are overlapping. 
D)  All of the above answers are correct.

Question 8

How do pennate muscles compare to fusiform or strap muscles with respect to ability to generate tension? What causes whatever differences to exist?

Accepted Answer

Fusiform and strap muscles have a large

Question 9

The soleus muscle exhibits which type of fiber arrangement?

Accepted Answer

A)  Fusiform 
B)  Unipennate 
C)  Bipennate 
D)  Multipennate 
A)  Fusiform 
B)  Unipennate 
C)  Bipennate 
D)  Multipennate

Question 10

The function of a Sharpey fiber is to:

Accepted Answer

A)  Attach the periosteum to the bone 
B)  Attach ligaments to capsules 
C)  Attach muscle to tendon 
D)  Attach tendon to bone 
A)  Attach the periosteum to the bone 
B)  Attach ligaments to capsules 
C)  Attach muscle to tendon 
D)  Attach tendon to bone

Question 11

The complete sarcomere unit lies within the boundaries of the ____________________.

Accepted Answer

A)  Z disks 
B)  A bands 
C)  H zone 
D)  M band 
A)  Z disks 
B)  A bands 
C)  H zone 
D)  M band

Question 12

Your patient attempts to strengthen his triceps by positioning his shoulder at the end of range of shoulder and elbow extension.He reports weakness and inability to extend his shoulder more in this position.His report may best be explained by which of the following?

Accepted Answer

A)  Active insufficiency of the biceps 
B)  Active insufficiency of the triceps 
C)  Passive insufficiency of the biceps 
D)  Passive insufficiency of the triceps 
A)  Active insufficiency of the biceps 
B)  Active insufficiency of the triceps 
C)  Passive insufficiency of the biceps 
D)  Passive insufficiency of the triceps

Question 13

The human body selectively recruits one size motor unit before another.Which size is recruited first,and why is this efficient?

Accepted Answer

Small motor units are recruited before l

Question 14

Name four components of a motor unit.In what ways can these components vary among motor units?

Accepted Answer

Anterior horn cell (AHC),axon,motor end

Question 15

Describe what happens to the angular velocity of a limb during a constant concentric muscle contraction when the load (resistance)is increased.Describe this in terms of net torque.

Accepted Answer

The limb will slow down.In a concentric

Question 16

In order to produce maximum torque for an isokinetic concentric contraction,should the speed of the motion be fast or slow? For an isokinetic eccentric contraction?

Accepted Answer

Isokinetic contractions are most commonl

Question 17

What protects the muscle from overcontraction or overstretch? What "monitors" length of a muscle?

Accepted Answer

Overcontraction and overstretch are prev

Question 18

Which of the following statements is true regarding connective tissue and muscle?

Accepted Answer

A)  Parallel elastic components only move after the muscle has completed a contraction. 
B)  Epimysium is an example of a series elastic component. 
C)  Parallel elastic components help to "uncrimp" the tendon. 
D)  A tendon is an example of a series elastic component. 
A)  Parallel elastic components only move after the muscle has completed a contraction. 
B)  Epimysium is an example of a series elastic component. 
C)  Parallel elastic components help to "uncrimp" the tendon. 
D)  A tendon is an example of a series elastic component.

Question 19

Maintaining a posture for a prolonged period of time requires muscles that are slow to fatigue and able to make small adjustments in muscle tension.Therefore,muscles with a high percentage of ________________muscle fibers would be very active during a maintained posture.

Accepted Answer

A)  Type I 
B)  Type IIB 
C)  Type IIA 
A)  Type I 
B)  Type IIB 
C)  Type IIA

Question 20

What must happen before a motor unit will fire (discharge)? What occurs immediately after discharge of the motor unit?

Accepted Answer

In order for a motor unit to discharge,t

Which of the following statements is true regarding cross-bridges?

Contrast active and passive insufficiency.Give examples of each using the same muscle.

When the body segments act in a closed kinematic chain,are muscles most commonly acting in normal or reverse action?

The elbow flexors will exert the greatest amount of torque/tension for which type of muscle contraction?

Your patient holds a weight in his right hand.Consider only the muscle activity of the elbow flexors.What type of muscle contraction would occur if T_M = 400 N,and T_L = 500 N,and motion is in the direction of elbow extension? (T_M = torque of muscle; T_L = torque of load)

Which of the following statements best describes the length-tension relationship of a muscle?

How do pennate muscles compare to fusiform or strap muscles with respect to ability to generate tension? What causes whatever differences to exist?

The soleus muscle exhibits which type of fiber arrangement?

The function of a Sharpey fiber is to:

The complete sarcomere unit lies within the boundaries of the ____________________.

Your patient attempts to strengthen his triceps by positioning his shoulder at the end of range of shoulder and elbow extension.He reports weakness and inability to extend his shoulder more in this position.His report may best be explained by which of the following?

The human body selectively recruits one size motor unit before another.Which size is recruited first,and why is this efficient?

Name four components of a motor unit.In what ways can these components vary among motor units?

Describe what happens to the angular velocity of a limb during a constant concentric muscle contraction when the load (resistance)is increased.Describe this in terms of net torque.

In order to produce maximum torque for an isokinetic concentric contraction,should the speed of the motion be fast or slow? For an isokinetic eccentric contraction?

What protects the muscle from overcontraction or overstretch? What "monitors" length of a muscle?

Which of the following statements is true regarding connective tissue and muscle?

Maintaining a posture for a prolonged period of time requires muscles that are slow to fatigue and able to make small adjustments in muscle tension.Therefore,muscles with a high percentage of ________________muscle fibers would be very active during a maintained posture.

What must happen before a motor unit will fire (discharge)? What occurs immediately after discharge of the motor unit?

Biomechanical Applications to Joint Structure and Function

Joint Structure and Function

The Vertebral Column

The Thorax and Chest Wall

The Temporomandibular Joint

The Shoulder Complex

The Elbow Complex

The Wrist and Hand Complex

The Hip Complex

The Knee Complex

The Ankle and Foot Complex

Filters

Exam 3: Muscle Structure and Function

Which of the following statements is true regarding cross-bridges?

Contrast active and passive insufficiency.Give examples of each using the same muscle.

When the body segments act in a closed kinematic chain,are muscles most commonly acting in normal or reverse action?

The elbow flexors will exert the greatest amount of torque/tension for which type of muscle contraction?

Your patient holds a weight in his right hand.Consider only the muscle activity of the elbow flexors.What type of muscle contraction would occur if TM = 400 N,and TL = 500 N,and motion is in the direction of elbow extension? (TM = torque of muscle; TL = torque of load)

Which of the following statements best describes the length-tension relationship of a muscle?

How do pennate muscles compare to fusiform or strap muscles with respect to ability to generate tension? What causes whatever differences to exist?

The soleus muscle exhibits which type of fiber arrangement?

The function of a Sharpey fiber is to:

The complete sarcomere unit lies within the boundaries of the ____________________.

Your patient attempts to strengthen his triceps by positioning his shoulder at the end of range of shoulder and elbow extension.He reports weakness and inability to extend his shoulder more in this position.His report may best be explained by which of the following?

The human body selectively recruits one size motor unit before another.Which size is recruited first,and why is this efficient?

Name four components of a motor unit.In what ways can these components vary among motor units?

Describe what happens to the angular velocity of a limb during a constant concentric muscle contraction when the load (resistance)is increased.Describe this in terms of net torque.

In order to produce maximum torque for an isokinetic concentric contraction,should the speed of the motion be fast or slow? For an isokinetic eccentric contraction?

What protects the muscle from overcontraction or overstretch? What "monitors" length of a muscle?

Which of the following statements is true regarding connective tissue and muscle?

Maintaining a posture for a prolonged period of time requires muscles that are slow to fatigue and able to make small adjustments in muscle tension.Therefore,muscles with a high percentage of ________________muscle fibers would be very active during a maintained posture.

What must happen before a motor unit will fire (discharge)? What occurs immediately after discharge of the motor unit?

Biomechanical Applications to Joint Structure and Function

Joint Structure and Function

The Vertebral Column

The Thorax and Chest Wall

The Temporomandibular Joint

The Shoulder Complex

The Elbow Complex

The Wrist and Hand Complex

The Hip Complex

The Knee Complex

The Ankle and Foot Complex

Filters

Your patient holds a weight in his right hand.Consider only the muscle activity of the elbow flexors.What type of muscle contraction would occur if T_M = 400 N,and T_L = 500 N,and motion is in the direction of elbow extension? (T_M = torque of muscle; T_L = torque of load)