Histo - 7 Nervous Tissue

Front 1

these structures provide protection, insulation, nourisment and support to neurons

Back 1

glia

Front 2

most peripheral ganglia have an origin from what, embryologically?

Back 2

neural crest

Front 3

what part of the neuron has the ability to transmit signals over long distances?

Back 3

axon

Front 4

what part of neuron receives info?

Back 4

dendrites

Front 5

neurons are postmitotic cells, which means what?

Back 5

unable to divide, once a neuron dies, it is not replaced

Front 6

why do sensory neurons tend to be round?

Back 6

bc they only have one process and no synaptic input

Front 7

size of neuron cell body

Back 7

4-120 microns

Front 8

general rule: large soma = ?

Back 8

large axon = fast conduction

Front 9

structure that contains the nucleus with abundant euchromatin actively transcribing DNA with prominent basophilic nucleus

Back 9

perikaryon

Front 10

structure of cell body that is the dominant cytoplasmic organelle, cisternae are grouped and interspersed with numerous free ribosomes that are actively synthesizing

Back 10

RER

Front 11

basophilic stained ribosomes as seen with light microscope

Back 11

Nissl bodies

Front 12

what indicates a highly active cell that is engaged in vesicular transport?

Back 12

numerous mitochondria and golgi

Front 13

microtubules in cell body are involved in what?

Back 13

vesicular transport

Front 14

neurofilaments in cell body are involved in what?

Back 14

cytoskeleton support

Front 15

what accumulates with age in cell body?

Back 15

lipofuscin granules

Front 16

proximally, what are the basic features of dendrites?

Back 16

same as cell body

Front 17

distally, what are the basic features of dendrites?

Back 17

Nissl substance decreases, cytoplasm is dominated by microtubules and smooth ER

Front 18

what is the branching pattern of dendrites that distinguishes each different neuronal type?

Back 18

taper and branch

Front 19

small extensions from dendrites that vary both in size and number among neurons and are receptive structures for axon terminals forming synapses

Back 19

dendrite spines

Front 20

what is the conduction pattern for most dendrites?

Back 20

they conduct potentials passively, in a decremental fashion over distance

Front 21

What area of the axon has no Nissl bodies?

Back 21

hillock

Front 22

main components of axon cytoplasm

Back 22

mostly microtubules and neurofilaments, no ribosomes or RER

Front 23

swellings at the axon's end which contact other neurons or excitable tissues, such as muscle cells, to transmit info

Back 23

axon terminals or boutons

Front 24

one neuron can receive up to how many axon terminals?

Back 24

up to 10,000

Front 25

type of transport that moves materials in the neuron and takes advantage of the cytoskeleton to do so. disrupting the skeleton stops transport.

Back 25

axoplasmic transport

Front 26

function of retrograde transport

Back 26

recycling and viral transport

Front 27

retrograde transport is mediated by what?

Back 27

cytoplasmic dynein

Front 28

anterograde transport is mediated by what?

Back 28

kinesin

Front 29

what structures perform fast anterograde transport (400 mm/day)?

Back 29

synaptic vesicles and mitochondria

Front 30

what structures perform slow anterograde transport (1-2mm/day)?

Back 30

proteins and enzymes, regrowing axons during regeneration

Front 31

the working end of the axon is called ?

Back 31

synapse

Front 32

3 distinct elements that contribute to the synaptic junction

Back 32

presynaptic membrane, axon terminal, postsynaptic membrane

Front 33

connection from axon to postsynaptic cell body is called?

Back 33

axosomatic

Front 34

from axon to postsynaptic dendrite is called?

Back 34

predendritic

Front 35

synapse bw axon and spine of dendrite is called?

Back 35

axospinous synapse

Front 36

interneuronal interactions that occur through gap junctions are called wat?

Back 36

nonsynaptic communication

Front 37

what is it called when all activity in one neuron would be transferred to the connected neuron w/o synaptic delay?

Back 37

nonsynaptic communication

Front 38

location of synaptic vesicles

Back 38

axon terminal

Front 39

which synaptic vesicles contain excitatory neurotransmitter?

Back 39

round vesicles

Front 40

which synaptic vesicles contain inhibitory neurotransmitter?

Back 40

polymorphic vesicles

Front 41

what is used to localize neurotransmitters or enzymes used in the synthesis of the neurotransmitters?

Back 41

immunocytochemistry and enzyme histochemistry

Front 42

function of peptide use in neurotransmission

Back 42

modulate effects of classical neurotransmitters

Front 43

examples of peptides used in neurotransmission

Back 43

LHRH, NPY, galanin, substance P

Front 44

groups of neural cell bodies in PNS

Back 44

ganglia

Front 45

groups of axons or sensory fibers in PNS

Back 45

nerves

Front 46

groups of cell bodies in CNS

Back 46

nuclei

Front 47

layers of cell bodies in CNS

Back 47

cortices

Front 48

groups of axons in CNS

Back 48

tracts, pathways, fasiculi

Front 49

everything except the cell bodies that is present in gray matter of CNS

Back 49

neuropil

Front 50

examples of neuropil

Back 50

dendrites, myelinated and unmyel axons, glial cells, blood vessels, synapses

Front 51

glial component of PNS comes from what, embryologically?

Back 51

neural crest

Front 52

these insulate peripheral axons and produce myelin

Back 52

schwann cells

Front 53

these insulate cell bodies in ganglia

Back 53

satellite cells

Front 54

CNS is mostly from what origin?

Back 54

neural tube

Front 55

these provide communication/insulation bw neurons and blood vessels and also insulate nodes of Ranvier and synaptic regions in CNS

Back 55

astrocytes

Front 56

these insulate central axons as the cells that make myelin sheaths which also produce a protein that actively inhibits regeneration in CNS

Back 56

oligodendrocytes

Front 57

phagocytic cell of CNS

Back 57

microglia

Front 58

origin of microglia

Back 58

bone marrow

Front 59

epithelial lining of fluid-filled space of CNS

Back 59

ependyma

Front 60

a single length of myelin along an axon

Back 60

internode

Front 61

groove at the end of Schwann cell wrapping

Back 61

inner and outer mesaxons

Front 62

process of compaction

Back 62

schwann cell cytoplasm is forced out of the membrane of myelin

Front 63

what structures are engulfed by a single glial process?

Back 63

unmyelinated axons

Front 64

major dense lines are formed by fusion of what?

Back 64

inner myelin membrane (3nm thick)

Front 65

intraperiod lines are formed by fusion of what?

Back 65

outer myelin membranes (1.5-2nm thick)

Front 66

what occurs where cell body undergoes breakup of RER and nuclear changes?

Back 66

retrograde chromatolysis

Front 67

what occurs as the distal axon fragment is separated from the metabolic support of the cell body?

Back 67

anterograde (wallerian) degeneration

Front 68

main components of PNS

Back 68

nerves and ganglia

Front 69

collections of sensory or autonomic neural cell bodies

Back 69

ganglia

Front 70

what are the plexuses of the PNS?

Back 70

cervical, brachial, lumbosacral, cardiopulmonary, preaortic, myenteric, hypogastic/pelvic

Front 71

what are splanchnic nerve pathways of PNS?

Back 71

thoracic, lumbar, sacral, pelvic

Front 72

node of ranvier in PNS is covered by what?

Back 72

schwann cell cytoplasm

Front 73

what is the outer collar of schwann cell cytoplasm called?

Back 73

neurolemma

Front 74

what covers an unmyelinated axon in the PNS?

Back 74

a single layer of schwann cell cytoplasm

Front 75

what forms connecive tissue sheaths (epineurium, perineurium, and endoneurium)?

Back 75

fibroblasts

Front 76

epineurium is made of what type of CT?

Back 76

dense CT

Front 77

characteristics of epineurium

Back 77

contains elastic fibers, retracts when cut, can be sutured

Front 78

whole fascicles are surrounded by perineurium that is made of what?

Back 78

squamous cells that form a semi-permeable barrier

Front 79

what is the function of tight junctions in the perineurium?

Back 79

prevent fluid buildup around axons

Front 80

what are the components of fascicles?

Back 80

groups of nerve fibers: axon + myelin + schwann cell cytoplasm and unmyelinated axons

Front 81

innermost connective tissue covering of nerves

Back 81

endoneurium

Front 82

what is endoneurium made of?

Back 82

collagen and reticular fibers

Front 83

what is an axonal injury distal to the cut that degenerates w/in 2 days in PNS and 2 weeks in CNS and the schwann cell tube remains?

Back 83

wallerian degeneration

Front 84

swelling of the cell body, eccentric nucleus, dissolution of Nissl bodies, production of large amount of protein for new axon is called...

Back 84

chromatolysis

Front 85

what bridges the gap at the injury site and directs neurites toward the schwann cell tube?

Back 85

schwann cell proliferation

Front 86

what causes phantom limb pain?

Back 86

failure of neurites to transverse the gap at an injury site which produces a neuroma

Front 87

sensory ganglia consist of:

Back 87

primary sensory neurons
DRG
Trigem ganglion
and in cranial neres 7, 8, 9, 10

Front 88

functions of autonomic ganglia

Back 88

visceral motility, control of smooth and cardiac musculature, secretion of glands

Front 89

what type of cells are sensory ganglia cell bodies?

Back 89

round pseudounipolar cell bodies

Front 90

pseudounipolar cell bodies are completely ensheathed by what?

Back 90

satellite cells

Front 91

function of satellite cells

Back 91

nutrition, insulation, metabolic and structural support

Front 92

autonomic ganglion cells have what type of cell bodies?

Back 92

multipolar cell bodies

Front 93

autonomic motor neurons are surrounded by...

Back 93

satellite cells

Front 94

main components of CNS

Back 94

spinal cord, brain stem nuclei, cortical brain structures

Front 95

major cell type of cerebral cortex

Back 95

pyramidal cells

Front 96

pyrimidal cell apical dendrites stretch to where?

Back 96

pial surface

Front 97

pyrimidal cell basilar dendrites branch in which direction?

Back 97

horizontally

Front 98

pyramidal cells occupy which cerebral cortex layers?

Back 98

3rd and 5th

Front 99

what types of cells are found ONLY in the caudal frontal cortex?

Back 99

giant pyramidal cells (of betz)

Front 100

what types of cells, other than pyramidal, are in cerebral cortex?

Back 100

fusiform, stellate, and granule cells

Front 101

cerebellum has how many layers of cortex?

Back 101

3

Front 102

major cell of cerebellum

Back 102

purkinje

Front 103

what type of cell is in the deepest layer of the cerebellum?

Back 103

granule cell

Front 104

pyramidal cells occupy which cerebral cortex layers?

Back 104

3rd and 5th

Front 105

what is the only obvious structure in astrocytes with Nissl staining?

Back 105

euchromatic nucleus

Front 106

what types of cells are found ONLY in the caudal frontal cortex?

Back 106

giant pyramidal cells (of betz)

Front 107

pyramidal cells occupy which cerebral cortex layers?

Back 107

3rd and 5th

Front 108

how do astrocytes look different than neurons?

Back 108

have light cytoplasm and smaller size

Front 109

what types of cells, other than pyramidal, are in cerebral cortex?

Back 109

fusiform, stellate, and granule cells

Front 110

astrocyte processes extend between what?

Back 110

blood vessels and neurons

Front 111

cerebellum has how many layers of cortex?

Back 111

3

Front 112

what part of astrocytes cover large neural and vascular areas?

Back 112

perivascular end feet

Front 113

what types of cells are found ONLY in the caudal frontal cortex?

Back 113

giant pyramidal cells (of betz)

Front 114

what types of cells, other than pyramidal, are in cerebral cortex?

Back 114

fusiform, stellate, and granule cells

Front 115

what protein is found in processes of astrocytes?

Back 115

glial fibrillary acidic protein (GFAP)

Front 116

major cell of cerebellum

Back 116

purkinje

Front 117

cerebellum has how many layers of cortex?

Back 117

3

Front 118

what type of cell is in the deepest layer of the cerebellum?

Back 118

granule cell

Front 119

structure found only in gray matter, surround neural soma and appear as fuzzy ball in silver stain

Back 119

protoplasmic astrocyte

Front 120

major cell of cerebellum

Back 120

purkinje

Front 121

what is the only obvious structure in astrocytes with Nissl staining?

Back 121

euchromatic nucleus

Front 122

what type of cell is in the deepest layer of the cerebellum?

Back 122

granule cell

Front 123

structure found mainly in white matter along tracts; spider-like appearance with silver stain

Back 123

fibrous astrocyte

Front 124

how do astrocytes look different than neurons?

Back 124

have light cytoplasm and smaller size

Front 125

what is the only obvious structure in astrocytes with Nissl staining?

Back 125

euchromatic nucleus

Front 126

astrocyte processes extend between what?

Back 126

blood vessels and neurons

Front 127

visual characteristics of oligodendrocytes

Back 127

dark cytoplasm, small dark staining nucleus, few processes

Front 128

what part of astrocytes cover large neural and vascular areas?

Back 128

perivascular end feet

Front 129

how do astrocytes look different than neurons?

Back 129

have light cytoplasm and smaller size

Front 130

6 differences of oligodendrocytes from schwann cells

Back 130

1. one olig wraps several axons
2. nodes of ranvier are larger and not covered by olig cytoplasm
3. few schmidt-lanerman clefts
4. no basal lamina
5. no cytoplasm in outer layer of myelin sheath
6. unmyelinated axons have no glial envelopment

Front 131

what protein is found in processes of astrocytes?

Back 131

glial fibrillary acidic protein (GFAP)

Front 132

structure found only in gray matter, surround neural soma and appear as fuzzy ball in silver stain

Back 132

protoplasmic astrocyte

Front 133

astrocyte processes extend between what?

Back 133

blood vessels and neurons

Front 134

structure found mainly in white matter along tracts; spider-like appearance with silver stain

Back 134

fibrous astrocyte

Front 135

what part of astrocytes cover large neural and vascular areas?

Back 135

perivascular end feet

Front 136

visual characteristics of oligodendrocytes

Back 136

dark cytoplasm, small dark staining nucleus, few processes

Front 137

what protein is found in processes of astrocytes?

Back 137

glial fibrillary acidic protein (GFAP)

Front 138

structure found only in gray matter, surround neural soma and appear as fuzzy ball in silver stain

Back 138

protoplasmic astrocyte

Front 139

6 differences of oligodendrocytes from schwann cells

Back 139

1. one olig wraps several axons
2. nodes of ranvier are larger and not covered by olig cytoplasm
3. few schmidt-lanerman clefts
4. no basal lamina
5. no cytoplasm in outer layer of myelin sheath
6. unmyelinated axons have no glial envelopment

Front 140

structure found mainly in white matter along tracts; spider-like appearance with silver stain

Back 140

fibrous astrocyte

Front 141

visual characteristics of oligodendrocytes

Back 141

dark cytoplasm, small dark staining nucleus, few processes

Front 142

6 differences of oligodendrocytes from schwann cells

Back 142

1. one olig wraps several axons
2. nodes of ranvier are larger and not covered by olig cytoplasm
3. few schmidt-lanerman clefts
4. no basal lamina
5. no cytoplasm in outer layer of myelin sheath
6. unmyelinated axons have no glial envelopment

Front 143

olig secrete a protein that does what?

Back 143

inhibits axon regeneration w/in CNS

Front 144

what structures are derived from blood cells and are phagocytic which help clear debris after injuries like a stroke?

Back 144

microglia

Front 145

what do microglia look like?

Back 145

small soma with nuclei, dark cytoplasm, exhibit many spikes

Front 146

what are cuboidal to columnar epithelial cells that line the ventricles and central canal of the CNS?

Back 146

ependyma

Front 147

specialized ependymal cells and associated capillaries that produce cerebrospinal fluid

Back 147

choroid plexus