Exam 5 Chapter 12

Front 1

nervous tissue consists of

Back 1

neurons and neuroglia

Front 2

what provides most of the unique functions of the nervous system

Back 2

neurons

Front 3

what controls sensing, thinking, remembering, controlling muscle activity, and regulating glandular secretions

Back 3

neurons

Front 4

what supports, nourishes, and protects the neuron and maintains homeostatis in the internstitial fluid that bathes them

Back 4

neuroglia

Front 5

what's specialized to react to physical and chemical changes in their surroundings

Back 5

neurons

Front 6

what receives the input

Back 6

dendrites

Front 7

what carries the information away from the cell in the form of nerve impulses

Back 7

axons or nerve fiber

Front 8

bundles of axons is termed

Back 8

nerves

Front 9

thought only to fill spaces and surround or support neurons

Back 9

neuroglial cells

Front 10

includes nourishing neurons and even sending and receiving messages

Back 10

neuroglial cells

Front 11

what are the 3 parts of a neuron

Back 11

dendrites
cell body
axon

Front 12

what is considered receptor fibers

Back 12

dendrites

Front 13

what conducts impulses to the cell body

Back 13

dendrites

Front 14

what contains the bulk of the cytoplasm and most of the organelles and nucleus

Back 14

cell body

Front 15

what carries signals away from the cell body

Back 15

axon

Front 16

what propagates nerve impulses toward anoehr neuron, a muscle fiber, or a gland cell

Back 16

axon

Front 17

what is the cytoplasm of an axon called:

what is surrounded by a plasma membrane known was the:

Back 17

axoplasm

axolemma

Front 18

synaptic vesicles store:

Back 18

neurotransmitter

Front 19

what has only two nerve fibers, one coming from each end:

which are:

Back 19

bipolar neurons

axon and dendrite

Front 20

what is found in the eyes, nose, and ears:

Back 20

bipolar neurons

Front 21

what kind of neuron is found in the ganglia:

Back 21

unipolar neurons

Front 22

what extends from the cell body then dividies into two branches:

the two branches are:

Back 22

unipolar neurons


dendrite and axon

Front 23

what is located outside the brain and spinal cord

Back 23

ganglia

Front 24

what has nerve fibers arising from their cell bodies

Back 24

multipolar

Front 25

only 1 fiber of each neuron is an axon and the rest are dendrities

Back 25

multipolar neuron

Front 26

most neurons whose cell bodies lie within the brain or spinal cord

Back 26

multipolar

Front 27

what conducts nerve impulses into the CNS

Back 27

sensory (afferent) neurons

Front 28

what connect with receptors that detect things outside and inside the body

Back 28

sensory (afferent) neurons

Front 29

what conducts impulses from the CNS to effectors (Skeletal, cardiac, smooth muscle, glands)

Back 29

motor nuerons

Front 30

what is located within the CNS

Back 30

interneurons

Front 31

what conveys messages between efferent and afferent parts of the system

Back 31

interneurons

Front 32

what contains 99% of neurons

Back 32

interneurons

Front 33

neuroglia do not generate or propagate

Back 33

action potentials

Front 34

out of the six types of neuroglia, four are found ONLY in the CNS which are

Back 34

AME-O

astrocytes
microglia
ependymal cells
oligodendrocytes

Front 35

the remaining two types of neuroglia which are located in the PNS are:

Back 35

schwann cells and satelite cells

Front 36

what fills spaces, provides structural frameworks, produces myelin, and carry on phagocytosis

Back 36

neuroglial cells

Front 37

the cells are scattered throughout the CNS where they phagocytize(get rid of) bacteria and debris

Back 37

microglial cells

Front 38

they usually increase in number whenever the brain or spinal cord is inflamed because of injury or disease

Back 38

microglial cells

Front 39

these cells commonly occur in rows along myelinated axons

Back 39

oligodendrocytes

Front 40

they form myelin in the brain and spinal cord

Back 40

oligodendrocytes

Front 41

can send out a number of processes, each of which forms a myelin sheath around a nearby axon

Back 41

oligodendrocytes

Front 42

what is commonly found between neurons and blood vessels

Back 42

astrocytes

Front 43

these cells provide structural support and protection

Back 43

astrocytes

Front 44

help regulate the concentrations of nutrients and ions within the tissue that fills spaces following injury to the CNS

Back 44

astrocytes

Front 45

cells located next to capillaries in brain

Back 45

astrocytes

Front 46

part of the bllod brain barrier

Back 46

astrocytes

Front 47

any cell of substance that enters the brain must pass through the walls of the __ and ___

Back 47

capillary and the astrocyte

Front 48

what lines the central canal of spinal cord, ventriciles, and choroid plexus

Back 48

ependymal cells

Front 49

what are cubodial or columnar in shape and have many cilia.

Back 49

ependymal cells

Front 50

they allow substances to diffuse freely between the interstitial fluid of the brain tissues and the CSF fluid

Back 50

ependymal cells

Front 51

PNS NEUROGLIA

make myelin sheath

Back 51

schwann cells

Front 52

PONS NEUROGLIA

support neurons in the PNS ganglia

Back 52

satellite cells

Front 53

what two types of neuroglia produce mylin sheath

Back 53

schwann cells in the PNS and oligodendrocytes in the CNS

Front 54

what speeds up nerve conduction down long fibers

Back 54

myelin sheath

Front 55

white lipid substances in the membrane of schwann cells and oligodengrocytes

Back 55

myelin sheath

Front 56

what acts to electrically insulate the axon

Back 56

myelin sheath

Front 57

what is characterized by patchy demyelination of axons in the CNS

Back 57

multiple sclerosis

Front 58

what is composed primarily of myelinated axons

Back 58

white matter

Front 59

what contains neuronal cell bodies, dendrites, unmyelinated axons, axons terminals, and neuroglia

Back 59

gray matter

Front 60

what matter is in the brain and spinal cord

Back 60

white

Front 61

what gives gray matter the gray color:

Back 61

nissil bodies and there is little or no myelin in the area

Front 62

neurons communicate with one another using two types of electrical signals:

Back 62

action potential and graded potential

Front 63

allows communication over both short and long distances within the body

Back 63

action potentials

Front 64

are used for short distance communication only

Back 64

graded potential

Front 65

production of actional potentials and graded potentials depends on two features of

Back 65

the plasma membrane and excitable cells which are:



the existence of a resting membrnae potential and the precense of ion channels

Front 66

the difference in electrical charge that exists across the membrane of every cell in the body

Back 66

membrane potential

Front 67

always negative in all cells at rest (inside of the cell is negative compared to the outside)

Back 67

membrane potential

Front 68

what has more negative ions on the inside of the cell

Back 68

membrane potentials

Front 69

what has a high conecntration of sodium ions present outside the neuron and a high concentration of potassium ions inside

Back 69

membrane potential

Front 70

membrane potentials contain specialized proteins called channels which does what

Back 70

forms pores in the membrane that are selectively permeavle to particular ions

for ex: sodium channels allow sodium ions through the membrane while potassium channels allow potassium ions though

Front 71

what gives neurons and muscle fibers the property of electrical excitability

Back 71

the presense of ion channels

Front 72

ions move from where they are more:

Back 72

concentrated to where they are less concentrated

Front 73

positively charged cations more toward

Back 73

a negatively charged area

Front 74

as ions move, they do what to change the membrane potential

Back 74

constitute a flow of electrical current

Front 75

most graded potentials occur in the

Back 75

dendrites and cell body

Front 76

a graded potential forms in response to the

Back 76

opening of mechanically gated channels or ligand-gated channels

Front 77

what kind of channel participates in the generation and conduction of action potentials

Back 77

voltage-gated channels

Front 78

a voltage gated channel opens in response to a change in the

Back 78

membrane potential

Front 79

ligand-gated channels open and close in response to a

Back 79

specific chemical stimulus

Front 80

what gate channel opens or closes in response to stimulation in the form of vibration, pressure, or tissure stretching

Back 80

mechanically-gated channel

Front 81

the resting membrane potential occurs when

Back 81

no electrical impulse is being conducted

Front 82

a small deviation from membrane potential that makes the membrane more or less polarized

Back 82

graded potential

Front 83

how does a graded potential arise

Back 83

when a stimulus causes ligand gated or mechanically gated channels to open or close in a cells plasma membrane

Front 84

what is a sequence of rapidly occuring events that takes place in two phases

Back 84

action potential

Front 85

during the depolarization phase the negative membrane potential

Back 85

decreases twoard 0 and becomes positive

Front 86

during the repolarizing phase, it restores what

Back 86

the membrane potential to the resting state of -70

Front 87

what channel = action potential

Back 87

voltage-gated channel

Front 88

during an action potential, 2 types of voltage gated channels open and then close.

the first channels that open are: and do what:

Back 88

sodium channels that allow sodium to rush into the cell which causes depolarization phase

Front 89

during an action potential, 2 types of voltage gated channels open and then close.

what is the second channel that opens called

Back 89

potassium channel opens, which allows potassium to flow out, which produces the repolaizing phase

Front 90

generation of action potential

stage 1

Back 90

resting state

voltage gated sodium and potassium ion channels are closed

Front 91

generation of action potentials

step 2

Back 91

depolarization phase

voltage gated sodium ion channels open and sdoium rushes into the cell

Front 92

generation of action potentials

step 3

Back 92

repolarization phase begins

voltag-gated sodium channels close. voltage gated postassium ion channels are open, and potassium leaves the cell

Front 93

generation of action potentials

step 4

Back 93

repolarization phase continues

voltage-gated sodium channels are closed. the voltage-gated potassium ion channels remain open longer than the sodium ion channels, thus more potassium ions leave the cell, producing hyperpolarization. the resting membrane potential is reestablished

Front 94

the existence of a resting membrane potential
and
the presence of specific types of ion channels

Back 94

production of action and graded potentials

Front 95

decreases toward 0 and becomes positive

Back 95

the negative membrane potential in the depolarization phase

Front 96

ions constitute a flow of electrical current that can change the

Back 96

membrane potential

Front 97

the membrane potential to the resting state of -70

what phase

Back 97

repolarizing phase

Front 98

what is the concentration of a membrane potential insidea nd outside the cell

Back 98

a high concentration of sodium ions present outside the neuron and a high concentration of potassium ions inside

Front 99

what maintains homeostasis in the interstitial fluid that bathes them

Back 99

neuroglia

Front 100

what supports, nourishes, and protects the neuron

Back 100

neuroglia