Nervous System Cells

Question 1

Central Nervous System consists of (2):

Answer 1

• Brain

- Spinal cord

Question 2

Structural and functional center of the nervous system that integrates sensory information

Answer 2

Central Nervous System

Question 3

Nerves that lie in “outer regions” of the nervous system

Answer 3

Peripheral Nervous System

Question 4

nerves that originate from the brain and brain stem (12 pairs)

Answer 4

cranial nerves

Question 5

nerves that originate from the spinal cord (31 pairs)

Answer 5

spinal nerves

Question 6

All incoming sensory pathways (northbound)

Answer 6

afferent division

Question 7

all outgoing motor pathways (southbound)

Answer 7

efferent division

Question 8

system that carries information to the skeletal muscle (or glands)

Answer 8

somatic motor division

Question 9

system that carries feedback information from skeletal muscle (or glands) to ____ integration centers in the CNS

Answer 9

somatic sensory division

somatic

Question 10

carries info to the visceral effectors (smooth and cardiac muscles and glands)

Answer 10

efferent division of autonomic nervous system

Question 11

carries feedback info to _____ integrating centers in the CNS

Answer 11

afferent/visceral sensory division

autonomic

Question 12

The autonomic nervous system is normally _____.

Answer 12

involuntary

Question 13

The somatic motor division is ____ and under conscious control.

Answer 13

voluntary

Question 14

2 subdivisions of efferent division of ANS:

Answer 14

• sympathetic division

- parasympathetic division

Question 15

prepares the body for immediate threats to its internal environment (fight, flight, or freeze response)

Answer 15

sympathetic division

Question 16

coordinates body’s normal resting activities (rest and repair)

Answer 16

parasympathetic division

Question 17

2 main types of cells in the nervous system:

Answer 17

• neurons

- glial cells (neuroglia)

Question 18

excitable cells that make nervous system functions possible. Form the “wiring” of the nervous system’s information circuits.

Answer 18

neurons

Question 19

cells that do not usually conduct information. They support the function of neurons in various ways.
(Helper cells)

Answer 19

glial cells (neuroglia)

Question 20

5 main types of glial cells:

Answer 20

• astrocytes
• microglia
• ependymal cells
• oligodendrocytes
• schwann cells

Question 21

star-shaped, largest, and most numerous type of glial cell. They transfer nutrients from blood to the neurons, help recycle neurotransmitters at synapses, and form tight sheaths around brain capillaries

Answer 21

astrocytes

Question 22

double barrier made up of astrocytes and the endothelial cells that make the capillary walls

Answer 22

blood-brain barrier, BBB

Question 23

The ________ helps maintain a very stable environment required for normal functioning of the brain by forming a barrier that regulates passage of most ions between the blood and brain tissue.

Answer 23

Blood-Brain Barrier, BBB

Question 24

Some ions could disrupt the transmission of nerve impulses if _____ did not exist.

Answer 24

Blood-Brain Barrier, BBB

Question 25

small, usually stationary cells that engulf and destroy microorganisms and cellular debris. The "Macrophages" of the nervous system.

Answer 25

Microglia

Question 26

____ are usually quiet and inactive, but if brain tissue is inflamed or degenerating, they will enlarge and become mobile, allowing them to carry out phagocytosis.

Answer 26

Microglia

Question 27

cells that form thin sheets that line fluid-filled cavities in the CNS. Some take part in producing the fluid that fills these spaces. Some have motile cilia that help circulate fluid.

Answer 27

ependymal cells

Question 28

The fluid filled cavities in the CNS

Answer 28

ventricles

Question 29

smaller than astrocytes with fewer processes. They hold nerve fibers together and produce the myelin sheath around nerve fibers in CNS only

Answer 29

Oligodendrocytes

Question 30

cells found only in the PNS. They support nerve fibers and form myelin sheaths.

Answer 30

Schwann cells

Question 31

gaps in the myelin sheath

Answer 31

Nodes of Ranvier

Question 32

where the nucleus and cytoplasm are squeezed to perimeter. Essential in normal growth and regeneration.

Answer 32

Neurolemma

Question 33

special schwann cells that surround the cell body of a neuron, usually in ganglia

Answer 33

satellite cells

Question 34

excitable cells that initiate and conduct impulses to make all nervous system functions possible

Answer 34

neurons

Question 35

The 3 components of a neuron:

Answer 35

- cell body - dendrites - axon

Question 36

AKA perikaryon or soma

Answer 36

cell body

Question 37

- provides neurotransmitters needed for transmission of nerve signals - provides proteins for maintaining and regenerating nerve fibers - contains mitochondria, which are transported to end of axon

Answer 37

cell body

Question 38

cells that do not have a myelin sheath, and conduct nerve signals to the cell body of the neuron

Answer 38

dendrites

Question 39

Each neuron has one or more _____, which branch from the cell body

Answer 39

dendrites

Question 40

portion of the cell body from which the axon extends

Answer 40

axon hillock

Question 41

part of neuron that conducts nerve impulses away from the cell body of the neuron. Is sometimes covered by a myelin sheath

Answer 41

axon

Question 42

zone where dendrites and cell body receive stimulus and initiates impulse

Answer 42

Input zone

Question 43

zone where axon hillock collects all the nerve impulses arriving from the cell body and dendrites and decides whether to send the impulse any farther along the neuron

Answer 43

summation zone

Question 44

zone where the axon conducts the nerve impulse from the axon hillock all the way to the end of the neuron

Answer 44

conduction zone

Question 45

zone where telodendria and synaptic knobs (release neurotransmitters)

Answer 45

output zone

Question 46

The 3 structural classifications of neurons:

Answer 46

- multipolar - bipolar - unipolar

Question 47

structural class: one axon and several dendrites

Answer 47

multipolar

Question 48

structural class: only one axon and one dendrite; least numerous kind of neuron

Answer 48

bipolar

Question 49

structural class: one process comes off neuron cell body but divides almost immediately into two fibers; central process and peripheral process

Answer 49

(pseudo)unipolar

Question 50

______ are always sensory

Answer 50

unipolar

Question 51

a signal conduction route to and from the CNS, with the electrical signal beginning in receptors and ending in effectors

Answer 51

reflex arc

Question 52

simplest form; consists of an aferrent neuron and an efferent neuron

Answer 52

two-neuron arc

Question 53

most common; consists of an afferent neuron, an interneuron, and an efferent neuron

Answer 53

three-neuron arc

Question 54

conduct impulses from afferent neurons to or toward motor neurons. They lie within CNS

Answer 54

Interneurons

Question 55

____ ____ are an example of regulatory feedback loop

Answer 55

Reflex arcs

Question 56

The location where nerve signals are transmitted from one neuron to another. Located at junction of synaptic knob of one neuron and dendrites or cell body of another neuron

Answer 56

synapse

Question 57

bundles of peripheral nerve fibers held together by several layers of connective tissue that form a sheath

Answer 57

nerves

Question 58

bundles of nerve fibers located within the CNS

Answer 58

tracts

Question 59

_____ : surrounds Schwann cell

Answer 59

endoneurium

Question 60

____ : surrounds a fascicle

Answer 60

perineurium

Question 61

____ : surrounds a whole nerve (and numerous fascicles and the blood vessels that supply them)

Answer 61

epineurium

Question 62

Most nerves in the nervous system are ____ ____, and contain both afferent and efferent fibers.

Answer 62

mixed nerves

Question 63

____ do not have connective tissue coverings.

Answer 63

tracts

Question 64

bundles of myelinated fibers

Answer 64

white matter

Question 65

made up of cell bodies and unmyelinated fibers

Answer 65

gray matter

Question 66

Gray matter: In the CNS bundles of cell bodies referred to as ____.

Answer 66

nuclei

Question 67

gray matter: In the PNS bundles of cell bodies referred to as ____.

Answer 67

ganglia

Question 68

____ have a limited capacity to repair themselves.

Answer 68

neurons

Question 69

Nerve fibers can be repaired if the damage is not extensive. The ____ and ____ have to be intact.

Answer 69

cell body, schwann cell

Question 70

1. The distal portion of the axon and the myelin sheath regenerate 2. Macrophages remove debris 3. Remaining neurolemma and endoneurium form tunnel from the point of injury to the effector 4. New schwann cells grow in the tunnel to maintain a path for regrowth of the axon 5. cell body reorganizes itself to provide the necessary proteins to extend the remaining healthy portion of the axon 6. axon sprouts appear. 7. Skeletal muscle cell atrophies until the nervous connection is reestablished

Answer 70

Stages of nerve repair

Question 71

CNS neurons lack the _____: no tunnel to guide the repair from the point of injury

Answer 71

neurolemma

Question 72

____ fill the damaged areas and block regrowth within the CNS

Answer 72

astrocytes

Question 73

Most injuries to the ____ and ___ cause permanent damage.

Answer 73

brain, spinal cord