Motor Functions

Question 1

Reflex

Answer 1

Unlearned response to a particular stimulus

Question 2

Motor Plan

Answer 2

A complex set of commands to muscles that is established before the behavior starts

Question 3

Closed-Loop Control Mechanism

Answer 3

Maximize accuracy

Information from whatever is being controlled flows back to the device that controls it

Question 4

Transducer

Answer 4

An element that measures output

Question 5

Error Detector

Answer 5

Measures difference between actual and desired output

Question 6

Open-Loop Control Mechanisms

Answer 6

Maximize speed

Activity is preprogrammed

Question 7

Smooth Muscles

Answer 7

A type of muscle fiber that is controlled by the autonomic nervous system rather than by voluntary control

Question 8

Antagonist Muscle

Answer 8

A muscle that counteracts the effect of another muscle

Question 9

Synergist Muscle

Answer 9

A muscle that acts together with another muscle

Question 10

Muscle Fibers

Answer 10

Work together under voluntary control

Question 11

Fast-Twitch Muscle Fibers

Answer 11

Contracts rapidly but fatigues easily (Legs)

Question 12

Slow-Twitch Muscle Fibers

Answer 12

Contracts slowly but does not fatigue easily

Question 13

Neuromuscular Junction

Answer 13

The region where the motor neuron terminal and adjoining muscle fiber meet
The point where the nerve transmits its message to the muscle fiber

Question 14

Innervation Ratio

Answer 14

Expresses the number of muscle fibers innervated by a single motor axon

Question 15

Proprioception

Answer 15

Body Sense

Information about the position and movement of the body that is sent to the brain

Question 16

Muscle Spindle

Answer 16

Sends impulses to the central nervous system when the muscle is stretched.

Question 17

Intrafusal Fiber

Answer 17

Small muscle fibers that lie within each spindle

Question 18

Extrafusal Fiber

Answer 18

One of the ordinary muscle fibers that lie outside the spindles and provide most of the force for muscle constriction

Question 19

Primary Sensory Ending

Answer 19

The axon that transmits information from the central portion of a muscle spindle

Question 20

Secondary Sensory Ending

Answer 20

The axon that transmits information form the ends of the muscle spindle

Question 21

Gamma Motor Neurons

Answer 21

Innervates the contractile tissue in a muscle spindle

Question 22

Alpha Motor Neurons

Answer 22

Controls the main contractile fibers (extrafusal fibers) of a muscle

Question 23

Stretch Reflex

Answer 23

1. Weight is added
2. The muscle is stretched
3. Afferents from the muscle spindle are excited
4. The spindle afferents connect directly to the motorneurons that control the stretched muscle, exciting them
5. The motorneurons stimulate the muscle to oppose muscle stretch

Question 24

Central Pattern Generator

Answer 24

Responsible for generating the rhythmic pattern of a behavior such as walking

Question 25

The Pyramidal System

Answer 25

Brain uses this system to send commands through the spinal cord

Question 26

Dystrophin

Answer 26

A protein needed for normal muscle function

Question 27

Ideomotor Apraxia

Answer 27

The inability to carry out a simple motor activity in response to a verbal command, even though this same activity is readily performed spontaneously

Question 28

Ideational Apraxia

Answer 28

An impalment in the ability to carry out a sequence of actions, even though each element and step can be done correctly