Deck 14: Determining the Force of a Muscle Contraction

Question 1

The strength of a muscle to create a joint action varies and is based:

A)solely on the muscle's sarcomere activity
B)solely on the leverage the muscle has on its attachments
C)on a combination of the intrinsic and extrinsic factors
D)on the number of nerve impulses coming to the muscle

Answer 1

on a combination of the intrinsic and extrinsic factors

Question 2

The best way to determine the strength of a muscle's contraction is by the number of:

A)motor units being recruited
B)muscle fibers contracting
C)sarcomeres contracting
D)actin-myosin cross-bridges formed

Answer 2

actin-myosin cross-bridges formed

Question 3

The Henneman size principle describes the:

A)order that muscles are recruited to contract
B)length tension relationship
C)order that motor units are recruited to contract
D)relationship between strength and size of a muscle

Answer 3

order that motor units are recruited to contract

Question 4

Which of the following can have a partial contraction?

A)muscle
B)motor unit
C)muscle fiber
D)sarcomere

Question 5

Which of the following characterizes the size of motor units?

A)Smaller motor units contract primarily for joint mobility.
B)Larger motor units contract primarily for joint stabilization.
C)No correlation exists between motor unit size and mobility versus stabilization function.
D)Smaller motor units contract for joint stability.

Question 6

Motor unit innervation includes that small motor units:

A)are innervated by large motor neurons
B)are innervated by small motor neurons
C)and large motor units are innervated by small motor neurons
D)and large motor units are innervated by large motor neurons

Question 7

Which of the following characterizes pennate muscles?

A)Only multipennate muscles have more than one central tendon.
B)Bipennate and multipennate muscles have more than one central tendon.
C)Bipennate muscles have two central tendons.
D)Unipennate muscles do not have a central tendon.

Question 8

Which of the following is used to determine the pulling strength of a pennate muscle on its attachment?

A)central tendon orientation
B)central tendon angle
C)pennation parameter
D)pennation angle

Question 9

What muscle architecture has its fibers arranged at an oblique angle to a central tendon?

A)strap
B)rhomboidal
C)triangular
D)pennate

Question 10

Which of the following muscle architectures have the fibers arranged in a featherlike pattern?

A)rhomboidal
B)fan shaped
C)pennate
D)spiral

Question 11

Smaller motor units are composed of:

A)white fast-twitch fibers
B)red slow-twitch fibers
C)an even mixture of white fast-twitch and red slow-twitch fibers
D)a majority of white fast-twitch and a small amount of red slow-twitch fibers

Question 12

Which of the following characterizes active and passive tension of a muscle?

A)Both active and passive tension is generated by the sliding filament mechanism.
B)Both active and passive tension is created by the muscular fascia.
C)Passive tension is generated by the sliding filament mechanism.
D)None of these choices is correct.

Question 13

What are the two major categories of muscle fiber architecture?

A)strap and rectangular
B)longitudinal and spiral
C)pennate and sphincter
D)pennate and longitudinal

Question 14

Which of the following is not a subcategory of pennate muscles?

A)unipennate
B)bipennate
C)polypennate
D)multipennate

Question 15

Which type of muscle architecture is best suited to create the largest range of motion?

A)longitudinal
B)unipennate
C)bipennate
D)multipennate

Question 16

What is another name for a fusiform muscle?

A)strap
B)spindle
C)rhomboidal
D)triangular

Question 17

Which of the following characterizes longitudinal and pennate muscles?

A)Pennate muscles have longer fibers.
B)Longitudinal muscles tend to have more fibers.
C)The fibers of pennate muscles are oriented along the length of the muscle.
D)Pennate muscles exhibit a greater strength over a shorter range of motion.

Question 18

During contraction,the order in which the motor units are recruited is:

A)small,medium,large
B)large,medium,small
C)dependent on the size of the muscle
D)without any particular order

Question 19

Muscular fascia creates what type of muscular tension?

A)active only
B)passive only
C)active and passive
D)neither active nor passive

Question 20

How many central tendons are located within a bipennate muscle?

A)one
B)two
C)three
D)variable number

Question 21

How many types of active insufficiency exist?

A)one
B)two
C)three
D)four

Question 22

A muscle with good leverage has what effect on motion of the body part?

A)greater strength and greater speed
B)lesser strength and lesser speed
C)greater strength but lesser speed
D)lesser strength but greater speed

Question 23

The disadvantage of increased leverage is that the:

A)power of the contraction is decreased
B)mechanical advantage is decreased
C)speed of motion of the body part is decreased
D)range of motion of the body part is decreased

Question 24

What term describes the fact that a multijoint muscle that shortens across one joint becomes weaker at its other joint or joints?

A)shortened active insufficiency
B)lengthened active insufficiency
C)active tension
D)passive tension

Question 25

The definition of a lever arm is the distance from the:

A)axis of motion to the distal end of the lever
B)axis of motion to the point of application of force on the lever
C)point of application of force on the lever to the distal end of the lever
D)distal end to the proximal end of the lever

Question 26

What class of lever has the force that causes motion and the force of resistance to motion on opposite sides of the axis of motion?

A)first
B)second
C)third
D)none of these choices

Question 27

Which of the following creates an internal force?

A)Thera-Bands
B)resistance tubing
C)muscle
D)gravity

Question 28

Active insufficiency of a muscle occurs as a result of fewer:

A)motor units contracted
B)muscle fibers recruited
C)myofibrils engaged
D)cross-bridges formed

Question 29

What are the three different length-tension relationship curves that are usually graphed?

A)shortened length,lengthened length,and total distance length
B)active tension,passive tension,and total tension
C)isometric,eccentric,and concentric
D)mobilization,stabilization,and neutralizing

Question 30

The sliding filament mechanism generates what type of muscular tension?

A)active only
B)passive only
C)active and passive
D)neither active nor passive

Question 31

When a multijoint muscle shortens across one joint,its pulling strength across the other joint or joints that it crosses becomes:

A)stronger
B)weaker
C)unchanged
D)developed

Question 32

Having fewer binding sites of actin available for myosin heads to attach to is described by what term?

A)passive tension
B)active insufficiency
C)Henneman size principle
D)pennation angle

Question 33

The graphed line that represents the pulling strength of a muscle at various lengths of the muscle is what type of relationship curve?

A)length-strength
B)tension-distance
C)distance-force
D)length-tension

Question 34

Elastic recoil of myofascial tissue plays a role in what type of tension?

A)active only
B)passive only
C)active and passive
D)neither active nor passive

Question 35

What class of lever has the force that causes motion and the force of resistance to motion on the same side of the axis of motion?

A)first
B)second
C)third
D)choices b and c

Question 36

Which of the following characterizes sarcomere length and actin-myosin cross-bridges?

A)Shorter sarcomeres have more actin-myosin cross-bridges.
B)Longer sarcomeres have more actin-myosin cross-bridges.
C)Sarcomeres at resting length have more actin-myosin cross-bridges.
D)Sarcomere length is independent of the number of actin-myosin cross-bridges.

Question 37

What do longer lever arms create?

A)mechanical advantage
B)velocity advantage
C)need for greater muscular contraction
D)increased range of motion of the joint

Question 38

What is the optimal angle of pull of a muscle on its bony attachment relative to the length (longitudinal axis)of the bone?

A)parallel
B)45 degrees
C)perpendicular
D)60 degrees

Question 39

What structures are levers in the human body?

A)muscles
B)tendons
C)bones
D)ligaments

Question 40

The distance from the axis of motion to the point of application of force on the lever is what type of arm?

A)lever
B)moment
C)effort
D)all of these choices

Question 41

What type of bending posture is the least healthy?

A)squat bend with the trunk vertical
B)stoop bend
C)squat bend with the trunk inclined forward
D)stoop bend with an aligned spine

Question 42

Which of the following word roots means to endure?

A)actus
B)levis
C)dolor
D)passivus

Question 43

A nonaxial movement has which class of lever?

A)first
B)second
C)third
D)none of these choices

Question 44

A seesaw is an example of what class of lever?

A)first
B)first and second
C)second
D)second and third

Question 45

If an object is held,its leverage:

A)varies depending on its weight
B)increases if it is farther from the body
C)decreases if it is farther from the body
D)does not change with the distance it is held from the body

Question 46

Which of the following word root means length?

A)transverso
B)longitudo
C)intrinsecus
D)multus

Question 47

Which of the following word roots means feather?

A)penna
B)avia
C)volo
D)bis

Question 48

What type of bending posture is the healthiest?

A)stoop bend
B)squat bend with the trunk inclined forward
C)squat bend with the trunk vertical
D)stoop bend with an aligned spine

Question 49

Which of the following characterizes leverage force for the different classes of levers?

A)Second-class levers have greater leverage than third-class levers.
B)Third-class levers have greater leverage than second-class levers.
C)Second- and third-class levers have the same leverage.
D)Sometimes second- and sometimes third-class levers have greater leverage.

Question 50

Which of the following characterizes second-class and third-class lever arms in the musculoskeletal system?

A)Second-class levers generate greater speed.
B)Third-class levers generate greater speed.
C)Third-class levers have greater mechanical advantage.
D)Second-class levers generate lesser mechanical advantage.

Question 51

Which type of bending posture puts the spinal joints into the open-packed position?

A)stoop bend
B)squat bend with the trunk inclined forward
C)squat bend with the trunk vertical
D)stoop bend with an aligned spine

Question 52

Which class of lever has the greatest leverage for the force that causes motion?

A)first-class
B)second-class
C)third-class
D)none of these choices

Question 53

A wheelbarrow is an example of what class of lever?

A)first and second
B)second
C)third
D)second and third

Question 54

Neck extensor musculature is an example of what class of lever?

A)first
B)first and second
C)third
D)second and third

Question 55

First-class levers,in relation to other classes of levers,generate:

A)greater speed than second-class levers
B)greater strength than third-class levers
C)greater strength and speed than second- and third-class levers
D)none of these choices

Question 56

At the elbow joint the triceps brachii muscle is an example of what class of lever?

A)first
B)first and second
C)third
D)second and third

Question 57

The brachialis muscle is an example of what class of lever?

A)first
B)first and second
C)third
D)second and third

Question 58

The effective weight of a 10-pound object held at arm's length away from the body is how many pounds?

A)1
B)10
C)40
D)70

Question 59

A pair of tweezers is an example of what class of lever?

A)first
B)first and second
C)third
D)second and third

Question 60

The soleus muscle is an example of what class of lever?

A)first and second
B)second
C)third
D)second and third

Question 61

Which of the following word roots means light?

A)tenseo
B)moveo
C)levis
D)penna

Question 62

Which of the following word roots means from without?

A)intrinsecus
B)extrinsecus
C)penna
D)longitude

Question 63

Which of the following word roots means to stretch?

A)tensio
B)actus
C)moveo
D)passivus