The Human Body Vocabulary (Chapter 7)

Front 1

*Nerves

Back 1

Bundles of axons and their sheaths which extend from the CNS

Front 2

*Ganglia

Back 2

Collections of neuron cell bodies which are outside of the CNS

Front 3

*Spinal nerves

Back 3

Nerves which originate from the spinal cord

Front 4

*Cranial nerves

Back 4

Nerves which originate from the brain

Front 5

*Afferent neurons

Back 5

Neurons which transmit action potentials from the sensory organs to the CNS

Front 6

*Efferent neurons

Back 6

Neurons which transmit action potentials from the CNS to the effector organs

Front 7

*Somatic motor nerous system

Back 7

The system that transmits action potentials from the CNS to the skeletal muscles

Front 8

*Autonomic nervous system

Back 8

The system that transmits action potentials from the CNS to the smooth muscles, cardiac muscles, and glands

Front 9

*Sympathetic division

Back 9

Division of the ANS that generally prepares the body for physical activity

Front 10

*Parasympathetic division

Back 10

Division of the ANS that regulates resting and nutrition-related functions such as digestion, defecation, and urination

Front 11

*Association neuron

Back 11

A neuron that conducts action potentials from one neuron to another neuron within the CNS

Front 12

*Excitability

Back 12

The ability to create an action potential in response to a stimulus

Front 13

*Potential difference

Back 13

A measure of the charge difference across the cell membrane

Front 14

CNS

Back 14

The central nervous system

Front 15

PNS

Back 15

Peripheral nervous system

Front 16

The central nervous system

Back 16

Composed of the brain and the spinal cord

Front 17

Peripheral nervous system

Back 17

composed of nerves and ganglia

Front 18

How many pairs of cranial nerves are there?

Back 18

12

Front 19

How many pairs of spinal nerves are there?

Back 19

31

Front 20

How many pairs of nerves are there in the PNS?

Back 20

43

Front 21

action potential

Back 21

An electrical signal that travels along a neuron

Front 22

Sensory division

Back 22

The afferenent division of the PNS

Front 23

motor division

Back 23

the efferent division of the PNS

Front 24

what are the two main divisions of the CNS?

Back 24

afferent and efferent division

Front 25

what are the two main parts of the efferent division?

Back 25

SMNS and ANS

Front 26

What are the two main divisions of the ANS?

Back 26

sympathetic and parasympathetic divisions

Front 27

What are the two types of cells in the nervous system?

Back 27

Neurons and neuroglia

Front 28

A neuron consists of which three parts?

Back 28

cell body, axons, dendrites

Front 29

Soma

Back 29

cell body

Front 30

What do dendrites do?

Back 30

bring messages in to the cell body

Front 31

What do axons do?

Back 31

send action potentials away from the cell body

Front 32

Where does the action potential begin?

Back 32

in the axon hillock

Front 33

myelin sheath

Back 33

a fatty wrapping that actually speeds up the transmission of the action potential down the axon

Front 34

schwann cells

Back 34

myelin sheaths near a neuron in the PNS

Front 35

oligodendrocytes

Back 35

myelin sheaths near a neuron in the CNS

Front 36

nodes of ranvier

Back 36

gaps in the myelin sheath

Front 37

collateral axons

Back 37

axons which have split

Front 38

terminal boutons

Back 38

presynaptic terminal

Front 39

unipolar

Back 39

a neuron with only one process

Front 40

bipolar

Back 40

a neuron with two processes: an axon and a single dendrite split into many branches

Front 41

multipolar

Back 41

a neuron with many process: several dendrites but only one axon

Front 42

unipolar neurons are in what part of the nervous system?

Back 42

afferent neurons

Front 43

bipolar neurons are in what part of the nervous system?

Back 43

specialized afferent neurons

Front 44

multipolar neurons are what sort of neurons?

Back 44

association neurons or motor neurons

Front 45

Neuroglia

Back 45

the 'connective tissue' of the nervous system; nine neuroglia per neuron

Front 46

Can neurons reproduce?

Back 46

No

Front 47

Can neuroglia reproduce?

Back 47

yes

Front 48

oligodendroctyes wrap around…

Back 48

…several axons

Front 49

schwann cells wrap around…

Back 49

…a portion of one axon

Front 50

Microglia

Back 50

neuroglia that engage in phagocytosis, acting like white blood cells in the brain and spinal cord

Front 51

Astrocytes

Back 51

neuroglia that form the blood-brain barrier

Front 52

What are the five types of neuroglia?

Back 52

Oligodendrocytes, Schwann cells, microglia, astrocytes, and ependymal cells

Front 53

blood-brain barrier

Back 53

a barrier that keeps blood (which is toxic to neurons) out of the brain

Front 54

What are the two types of ependymal cells?

Back 54

ciliated and non-ciliated cells

Front 55

What do non-ciliated ependymal cells do?

Back 55

secrete cerebrospinal fluid

Front 56

What do ciliated ependymal cells do?

Back 56

move the cerebrospinal fluid to keep it homogenous

Front 57

Cerebrospinal fluid

Back 57

a fluid secreted by non-ciliated ependymal cells that bathes the spinal cord tissue and the brain while providing a protective cushion around the CNS

Front 58

Epineurium

Back 58

a shiny wrapping that encloses several fascicles

Front 59

Perineurium

Back 59

a wrapping that encloses one fascicle

Front 60

endoneurium

Back 60

a wrapping that encloses one axon

Front 61

Fascicle

Back 61

a bundle of axons

Front 62

sensory nerve

Back 62

a nerve that only carries information from receptors

Front 63

motor nerve

Back 63

a nerve that only carries information to effectors

Front 64

mixed nerve

Back 64

a nerve that carries information from receptors and information to effectors

Front 65

What two things must happen if a neuron will regenerate?

Back 65

It must be pointed in the right general directions and the myelin sheath must undergo mitosis and form a pathway to the other neuron

Front 66

Which myelin neuroglia can form a path for an injured axon?

Back 66

Schwann cells

Front 67

Which cells can be healed to a certain extent?

Back 67

neurons in the PNS that have Schwann cells around their axons

Front 68

Action potential

Back 68

an electrical signal; a disturbance of the membrane, caused by ions and their interactions with other ions

Front 69

During the resting potential, which part of the neuron is negative?

Back 69

the inside

Front 70

Resting potential

Back 70

The difference between the inside and outside charge of the neuron when an action potential is not being sent

Front 71

polarized

Back 71

separated - the neuron is polarized when at rest because the inside charge is separated from the outside charge

Front 72

why is the membrane polarized when at rest?

Back 72

The large proteins are too big to diffuse out

Front 73

sodium-potassium exchange pump

Back 73

the process by which sodium ions are pushed out of the axon while potassium ions are pulled into it

Front 74

what is the 'exchange rate' for sodium ions to potassium ions?

Back 74

three sodium per two potassium

Front 75

which ions tend to enter/leave the axon on their own?

Back 75

the potassium ions

Front 76

What is the resting potential of a neuron?

Back 76

-85 mV

Front 77

In order to get an action potential, there must be a…

Back 77

stimulus

Front 78

What are types of stimuli?

Back 78

neurotransmitters, movement, light, heat, chemicals, and electricity

Front 79

depolarization

Back 79

the process by which the potential difference changes from -85 mV to +30 mV

Front 80

repolarization

Back 80

the process by which the potential difference changes from +30 mV to slightly less than -85 mV

Front 81

local potential

Back 81

a small change in the potential difference which just dies out because the stimulus which produced it was subthreshold

Front 82

Refractory period

Back 82

The time when no action potential can be generated on the neuron because one is already in progress

Front 83

Absolute refractory period

Back 83

the refractory period when, no matter how large the stimulus, no action potential will be generated

Front 84

Relative refractory period

Back 84

the refractory period when the neuron is not ready to create an action potential, but, if the stimulus is strong enough, it will.

Front 85

unmyelinated axon

Back 85

two Schwann cells encompass several axons

Front 86

myelinated axon

Back 86

Two Schwann cells encompass one axon

Front 87

Continuous conduction

Back 87

conduction of an action potential where each action potential stimulates the response of the next little section of the axon.

Front 88

saltatory conduction

Back 88

conduction of an action potential where the action potential 'leaps' over the myelin sheath.

Front 89

pre-synaptic neuron

Back 89

the neuron that is sending an action potential to another neuron

Front 90

post-synaptic neuron

Back 90

the neuron that is receiving an action potential from another neuron

Front 91

neuromuscular junction

Back 91

a neuron-to-muscle synapse

Front 92

inhibatory synapse

Back 92

a synapse that stops information from passing to the next neuron

Front 93

EPSP

Back 93

Excitatory postsynaptic potentials

Front 94

IPSP

Back 94

Inhibitory postsynaptic potentials

Front 95

temporal summation

Back 95

an action potential is created by temporal summation by an axon carrying several action potentials within a small amount of time

Front 96

spatial summation

Back 96

an action potential is created by temporal summation by several axons each carrying an action potential

Front 97

hyperpolarization

Back 97

The change that takes the neuron farther away from being able to create an action potential

Front 98

What are the three types of neuron arrangements?

Back 98

Convergent, divergent, and oscillating

Front 99

convergent neuron arrangement

Back 99

many inputs lead to one limited output

Front 100

Divergent neuron arrangement

Back 100

One message gets spread to different parts of the body

Front 101

Oscillating neuron arrangement

Back 101

The message regenerates itself

Front 102

After-discharge response

Back 102

the process by which a neuron sends an action potential to itself, thus causing the potential to begin again.