Deck 4: The Neuromuscular Basis of Human Motion

Question 1

Which is an example of a typical crossed-extensor response?

A) unweighting of one foot in response to pressure on the other
B) contraction of the extensor muscles in response to deep pressure on the foot
C) contraction of the extensor muscles of one leg in response to unweighting of the opposite foot
D) reflex extension of the arm when the leg extends

Answer 1

contraction of the extensor muscles of one leg in response to unweighting of the opposite foot

Question 2

Which is an example of the phasic stretch reflex?

A) the use of a wind-up in throwing
B) the head position in a volleyball spike
C) lower extremity extension in walking
D) the ready position in tennis

Answer 2

the use of a wind-up in throwing

Question 3

What are two mechanisms the body uses to regulate the strength of muscle contractions?

A) use more muscles and a greater force
B) recruit more motor units and increase firing rate
C) recruit more motor units and contract harder
D) increase firing rate and strength of fiber

Answer 3

recruit more motor units and increase firing rate

Question 4

Which movement inhibits the crouched position at the beginning of a standing long jump?

A) flexion of the arms
B) flexion of the head
C) dorsi flexion of the feet
D) hyperextension of the head

Question 5

Which of the following is the function of the muscle spindle?

A) receiving impulses from joint actions
B) receiving stimuli from increased muscle tension
C) transmitting impulses to motor unit
D) transmitting sensations to the cerebral cortex

Question 6

Which of the following head and neck positions would facilitate the desired movement or position?

A) extension of head during landing in a volleyball spike
B) flexion of head just prior to take off in a long jump
C) hyperextension of head in a head stand
D) flexion of head in a back dive

Question 7

What type of neurons conduct impulses from the stimulus toward the spinal cord?

A) afferent
B) efferent
C) ganglia
D) spinal nerves

Question 8

What is a motor unit?

A) myoneural junction
B) a single motor neuron and all of the muscle fibers it innervates
C) a structured neuromotor sensory feedback unit
D) functional afferent nerve trunk and all of its receptors

Question 9

Where is the cell body of a motor neuron located?

A) motor unit
B) ventral horn of spinal cord
C) dorsal root ganglion
D) pre-ganglion

Question 10

Which reflex would be most likely to inhibit the performance of a forward roll?

A) tonic neck reflex
B) body righting reflex
C) Golgi tendon organ response
D) extensor thrust reflex

Question 11

Which of the following illustrates the use of the tonic stretch reflex to facilitate a motor act?

A) continuous movement of arm back and then forward in bowling
B) long, fast backswing in a golf drive
C) rapid backswing preceding a hard overhand throw
D) short, relatively slow backswing in a golf putt

Question 12

Which of the following is most sensitive to linear acceleration?

A) utricle
B) free nerve endings
C) semicircular canals
D) neck receptors

Question 13

Which of the following is a tonic neck reflex pattern when the head turns right?

A) right upper arm extends, left elbow flexes
B) left arm abducts, right arm adducts
C) left arm adducts, right arm abducts
D) right arm adducts, right elbow extends

Question 14

Which category best represents the receptors that receive and transmit impulses from muscles, joints, and tendons?

A) exteroceptors
B) interoceptors
C) visceroceptors
D) proprioceptors

Question 15

What is the purpose of the gamma efferent system?

A) adjusts the length of extrafusal muscle fibers thereby relieving tension on muscle spindle
B) makes muscle spindle more sensitive to external stretch therefore facilitating more effective muscle contraction
C) relays impulses from other proprioceptors to muscle spindle
D) transmits impulses from muscles to central nervous system and back to the muscles

Question 16

Which of the following proprioceptors is sensitive to the stimulus that results in an extensor thrust reflex response?

A) Golgi tendon organ
B) muscle spindle
C) Pacinian corpuscle
D) Ruffini ending

Question 17

What is the phasic stretch reflex?

A) quick, phasic response of muscle due to decrease in muscle tonus
B) reflex contraction of muscle due to the response of muscle spindles to an increase in muscle tension
C) reflex relaxation of muscle due to the inhibitory response to stimuli from proprioceptors
D) sustained static contraction of muscle due to effect of gravity on body

Question 18

Which head position would facilitate elbow flexion?

A) flexion and rotation to same side
B) flexion and rotation to opposite side
C) hyperextension and rotation to same side
D) hyperextension and rotation to opposite side

Question 19

In which of the following does the stretch reflex facilitate the movement defined?

A) horizontal abduction of the shoulder facilitates the forward swing of the throwing arm
B) extension of the elbow joint facilitates the pushup
C) flexion of the knee facilitates the down phase of a squat lift
D) rotation of the spine facilitates the backswing in golf

Question 20

Which of the following proprioceptors is sensitive to joint angle changes?

A) Pacinian corpuscle
B) Ruffini endings
C) muscle spindle
D) Golgi tendon organ

Question 21

Where are movement patterns remembered?

A) brain stem
B) cerebellum
C) cerebral cortex
D) basal ganglia
Short Answer Questions

Question 22

Where does a gymnast initiate the contraction of the many muscles involved in performing a roll?

A) cerebellum
B) pons
C) cerebral cortex
D) occipital lobe

Question 23

Which of the following best describes the phenomenon of reciprocal inhibition?

A) agonist contracts, neutralizers contract
B) agonist contracts, antagonist contracts
C) agonist contracts without opposition from antagonist
D) agonist contracts, synergist contracts

Question 24

Why might an elderly person press their hands against their thighs when attempting to rise from a seated position?

Question 25

What is the phenomenon which causes the tension in antagonistic muscles to be less during movement?

A) neutralization
B) proprioceptive inhibition
C) reciprocal innervation
D) stretch reflex

Question 26

A subject's feet are kept in a bucket of ice water for an extended period of time. The feet are removed from the bucket and the subject jumps off a chair with eyes closed. The subject falls upon landing. Why?

Question 27

What reflexes might interfere with teaching a beginner to do a standing front dive?
Explain both the reflexes and the effect.

Question 28

Provide a neuromuscular explanation for why is it easier to do a handstand if the head and neck are hyperextended than if they are not.

Question 29

When landing from a jump, which of the following proprioceptors facilitate the return to the standing position?
1) Pacinian corpuscles
2) joint receptors in feet
3) labyrinthine system
4) muscle spindles

A) 1, 2, 3
B) 1, 2, 4
C) 1, 3, 4
D) 2, 3, 4

Question 30

Disregarding arm motion, why is it easier to jump higher if one flexes the lower extremity and then immediately extends, with no hesitation between motions?