Lyons Nova Phs4904 Nervous System Ch7

Front 1

A grouping of cell bodies located within the central nervous system is known as ________

Back 1

ganglion

Front 2

The numerous small extensions from the soma are known as the __________.

Back 2

dendrites

Front 3

A _____ neuron transmits impulses from the CNS to the PNS.

Back 3

motor

Front 4

An association neuron is located entirely within the _____ nervous system.

Back 4

central

Front 5

Voluntary effectors (skeletal muscle) are innervated by _____motor neurons.

Back 5

somatic

Front 6

Sensory neurons (or afferent neurons) transmits impulses from the _____ to the _____ nervous system

Back 6

periphery to the central

Front 7

Myelin sheaths around axons located within the CNS (central nervous system) are formed by ______________.

Back 7

oligodendrocytes

Front 8

_______ form myelin sheaths around axons in the PNS

Back 8

Schwann cells

Front 9

______ migrate throughout the CNS and phagocytize foreign and degenerated material.

Back 9

Microglia

Front 10

_____ help to regulate the external environment of neurons in the CNS.

Back 10

Astrocytes

Front 11

Which is not a supporting cell or glial cell of the nervous system? A) Schwann cell, B) oligodendrocyte, C) ependymal cells, or D) assoc. neurons

Back 11

association neuron is a type of neuron not a type of glial cell.

Front 12

Arrange these action potential events in their proper sequence:
1. threshold voltage is reached
2. K+ gates begin to open
3. K+ gates close
4. Na+ gates begin to open
5. Na+ gates begin to close
6. membrane repolarization begins.

Back 12

D) 1,4,2,5,6,3

Front 13

The diffusion of K+ out of cell makes the inside of cell less positive,(or more negative), & acts to restore original resting mb pot. This process is called _____________.

Back 13

repolarization

Front 14

Nerve impulses are conducted along an axon without decrement. This means the action potentials are conducted without ____________.

Back 14

decreasing amplitude

Front 15

A __________ is a synapse between a somatic motor neuron and a skeletal muscle fiber.

Back 15

neuromuscular junction

Front 16

______ synapses require the presence of gap junctions

Back 16

electrical

Front 17

_______ are water-filled channels through which ions can pass from one cell to another permitting impulses to be conducted directly from one cell to another

Back 17

Gap junctions

Front 18

Acetylcholinesterase is an enzyme located on or immediately outside the _________.

Back 18

postsynaptic mb

Front 19

does the AP produced at the last region of the axon have the same amplitude as the AP at the first region of the axon?

Back 19

yes

Front 20

The 1st voltage-regulated gates encountered along the neuron mb, which initiate formation of action pot., are located on the neuron near the _______________.

Back 20

axon hillock

Front 21

Cocaine stimulates the synapses of specific neurons that release dopamine & other monoamines, by ______________.

Back 21

blocking the dopamine or monoamine reuptake into the presynaptic axon ending

Front 22

The central nervous system (CNS) includes the brain and _____

Back 22

spinal cord

Front 23

______ are the functional units of the nervous system by which they initiate, conduct, & transmit nerve impulses.

Back 23

Neurons

Front 24

_______ cells are supporting cells for the neurons.

Back 24

neuroglia

Front 25

Can a nerve contain both sensory and motor neurons?

Back 25

yes, a mixed nerve

Front 26

Capillaries in the brain are joined together by ______. This helps to form the BBB.

Back 26

tight junctions

Front 27

A(An) ________ neuron transmits impulses from the PNS to the CNS.

Back 27

sensory

Front 28

Involuntary effectors (glands, smooth or cardiac muscle) are innervated by _________neurons.

Back 28

autonomic neurons

Front 29

Afferent pathways are __(motor/sensory)__ & transmit impulses _(to/from)__ the CNS

Back 29

sensory, to

Front 30

what is the morphological difference betw. grey matter & white matter?

Back 30

gray-cell bodies & dendrites Vs white-myelinated axons

Front 31

which would contain the highest density of voltage gated Na+ channels? A) dendrites, B) soma C) nodes of Ranvier D) internodes E) synaptic end bulbs

Back 31

C) nodes of Ranvier

Front 32

what is the major extracellular cation?

Back 32

Na+

Front 33

An IPSP is _(hyperpolarization /repolorization/ depolarization?)___ of the postsynaptic neuron.

Back 33

hyperpolorization

Front 34

Saltatory conduct occurs only in ________

Back 34

myelinated nerve fibers

Front 35

neurons communicate specifically through chemicals called _______

Back 35

neurotransmitters

Front 36

explain how one way transmission of signal conduction is insured on an axon:

Back 36

absolute refractory period

Front 37

which glial cell forms a myelin sheath in the PNS?

Back 37

schwann cells

Front 38

which glial cell forms a myelin sheath in the CNS?

Back 38

ogliodendrocytes

Front 39

which glial cells remove pathogens & cell debris from phagocytosis?

Back 39

mircroglia

Front 40

which glial cells form the BBB?

Back 40

astrocytes

Front 41

what is 1 essential difference betwe the Somatic motor & the Autonomic motor?

Back 41

somatic- voluntary VS autonomic- involuntary

Front 42

what will occur when a neuron is depolarized to threashold?

Back 42

voltage-gated Na+ channels open

Front 43

what is a nerve?

Back 43

bundle of axons-PNS

Front 44

what are the cells of the PNS?

Back 44

satellite & schwann

Front 45

what is the function of satellite cells?

Back 45

support ganglia cell bodies in PNS

Front 46

what is the function of schwann cells?

Back 46

form myelin sheath successive wrapping of cmb- PNS

Front 47

how many axons do schwann cell wrap around?

Back 47

1 axon only

Front 48

what is neurilemma?

Back 48

continuous sheath of schwann cells- surrounds axon- can be myelinated or unmyelinated

Front 49

where can neurilemma be found?

Back 49

PNS only

Front 50

is neurilemma myelinated or unmyelinated?

Back 50

can be either

Front 51

___unmyelinated? /myelinated?___ usually have small axons

Back 51

unmyelinated

Front 52

myelinated vs unmyelinated, which are faster?

Back 52

myelinated

Front 53

what supporting cell in PNS has the ability to regenerate?

Back 53

schwann

Front 54

which cell has limited ability to regenerate in CNS?

Back 54

oligodendrocyte

Front 55

what must be intact for axon to regenerate in schwann cell?

Back 55

cmb

Front 56

what are the 4 supporting cells (glia) of the CNS?

Back 56

Oligodendrocytes, Microglia, Astrocytes, Ependymal

Front 57

where is the gray matter in the brain located?

Back 57

cell bodies & dendrites

Front 58

when does CNS myelination occur in the human body?

Back 58

post natally

Front 59

how many axons do oligrodendrites myelinate?

Back 59

several

Front 60

what is the white matter in the brain?

Back 60

myelinated axons CNS

Front 61

can axons repair in CNS?

Back 61

limited- oligodendrites: 1.inhibitory proteins (myelination) 2. glial scar

Front 62

what is the effect of a glial scar?

Back 62

physically blocks oligodendrites from repairing axon & induces inhibitory proteins

Front 63

what is the beneficial function of microglia?

Back 63

they are resident macrophages- secrete antiinflammatory (brain)

Front 64

what are the implications of microglia?

Back 64

overactivity can cause neurodegeneration

Front 65

what are the end feet?

Back 65

astrocytes

Front 66

what are 3 functions of neurons?

Back 66

responsive, conductivity, secretory

Front 67

can neurons divide?

Back 67

not regularly, most are postmitotic & G0

Front 68

can glia divide?

Back 68

yes, considered mitotic, but limited

Front 69

what are the predominant cells in the nervous sys?

Back 69

supporting cells (glia/glial) outnumber neurons 5:1

Front 70

a neuron is composed of ____

Back 70

cb, axon, & dendrites

Front 71

what is the nutrition center?

Back 71

cb of neuron where macromolecules are produced

Front 72

where are the nissl bodies & nucleus contained?

Back 72

cb

Front 73

what are gliomas?

Back 73

mitotic glia cells produce brain tumor

Front 74

what are nissl bodies?

Back 74

in cb, have RER for syn of mb proteins

Front 75

collection of cell bodies within CNS is called _____

Back 75

nuclei (not to be mistaken for nucleus)

Front 76

collection of cb outside CNS is called ______

Back 76

ganglia (basil ganglia-nuclei in brain)

Front 77

what are the receptive processes?

Back 77

dendrites

Front 78

what are the functions of axons?

Back 78

conduct impulse

Front 79

where is the origination of impulse?

Back 79

axon hillock

Front 80

what are axon collaterals?

Back 80

branchings located on some axons

Front 81

how long are axons?

Back 81

mm-m

Front 82

what is the BBB?

Back 82

capillaries to brain not porous, tight junctions, selective barrier

Front 83

how is molecule transport conducted to and from brain? (4)

Back 83

diffusion, active trans, endocytosis, & exocytosis

Front 84

through BBB __para/transcellular?__ is perdominant

Back 84

transcellular predominant.....paracellular is restricted

Front 85

what can pass the BBB easy?

Back 85

lipid soluble mo, O2, CO2, alcohol, barbiturates

Front 86

how are ions & polar mo transported through BBB?

Back 86

channels or transporters, GLUT1