CH 19 Pt 1

Question 1

CNS

Answer 1

Analyze and organizes info
-motor system planning and commands
MAINLY SENSORY

Question 2

PNS

Answer 2

Outputs CNS commands and sends sensory info to CNS
PRIMARILY MOTOR

Question 3

Cerebellum

Answer 3

Primary motor cortex inside
-motor control centre

Question 4

Afferent Neurons

Answer 4

Relay sensory info from peripheral to the CNS along posterior column
-away from muscles

Question 5

Efferent Neuons

Answer 5

Relay info from CNS to the peripheral or away from the brain along the pyramidal tract
Somatic: voluntary
Autonomic: involuntary

Question 6

Which brain region is associated with processing of sensory signals

Answer 6

Parietal love

Question 7

Which art of brain is the primary motor cortex?

Answer 7

Pre -central gyrus

Question 8

Which part connects each brain hemisphere via commisural fibers

Answer 8

Corpus callosum

Question 9

Which part of the brain is known as the motor control centre

Answer 9

cerebellum

Question 10

The what roots of the spinal cord contain what neurons that relay info back to the CNS?

Answer 10

The dorsal roots contain Afferent neurons

Question 11

Voluntary Movements

Answer 11

Require integration at the cerebral cortex
-learned movements may become reflexive
-muscle memory

Question 12

Reflexive Movements

Answer 12

Sensory input (vision, vestibular, muscle)
-can be modulated by higher brain centres
-involved in posture

Question 13

Rhythmic Movements

Answer 13

Voluntary and reflexive
-initiated by cerebral cortex
-can be sustained without input from brain

Question 14

CPG

Answer 14

Central Pattern Generator
-neural network in the lower part of the spinal cords that is thought to control locomotion
-doesn’t require input from higher brain
-output can be modified by input from brain or reflexes

Question 15

Reflex Arc

Answer 15

Basic mechanism to process autonomic muscle action
-peripheral stimulus causes Afferent neuron impulses to enter spinal cords

Question 16

Reflex Arc pathway

Answer 16

Afferent neurons interconnect (synapse) with interneurons in the spinal cord to relay info to CNS
Efferent signals return via anterior motor neurons to the muscles
Muscle responds

Question 17

Motor Unit represents:

Answer 17

An alpha motor neuron and the fibers that it innnervates

Question 18

Motor Neuron Pool represents

Answer 18

A collection of alpha motor neurons that innervate ONE muscle

Question 19

Small Motor Unit

Answer 19

Only have a few fibers/ motor neurons
(small/ fine movements)

Question 20

Large Motor Unit

Answer 20

May have hundreds or thousands of muscle fibers/ motor neurons
-simple, but gross movements

Question 21

All muscle fibers within a given motor unit are:

Answer 21

The same fiber type (1, 2a, 2x)

Question 22

Dendrites

Answer 22

Receive impulses and direct toward cell body

Question 23

Cell body

Answer 23

Control centre

Question 24

Schwaan cell

Answer 24

Covers bare axon

Question 25

Schwaan cell

Answer 25

Covers bare axon

Question 26

Myelin sheath

Answer 26

Electrical insulator of the axon

Question 27

Neurilemma

Answer 27

Membrane covering the myelin sheath

Question 28

Nodes of ranvier

Answer 28

Permit depolarization of axon

Question 29

Nodes of ranvier…

Answer 29

Allow reinforcement of the current strength, but the current flows slower in these sections

Question 30

The more myelin or the thicker the axon,

Answer 30

The faster conduction velocity of the axon

Question 31

Motor Endplate:

Answer 31

Neuromuscular Junction
Interface/ junction between the end of a motor neuronal excitability CNS and muscle fiber
-transmits nerve impulses to initiate muscle action

Question 32

Anatomical features of a neuromuscular junction

Answer 32

Pre synaptic terminals
-synpatic cleft
-post synaptic membrane