Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

EXAM 2 - Anatomical Sciences > Nerves > Flashcards

Nerves Flashcards

1
Q

What are the two parts of the nervous system?
What make up each?

A

Central - spinal cord and brain
Peripheral - sensory elements that conduct information into CNS and motor elements that conduct signals from the CNS to effector cells (muscles, glands, viscera)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the effectors of the somatic nervous system

A

Skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the effectors of the autonomic nervous system

A

Smooth muscle, cardiac muscle, glands, adipose tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In general, ____ receive information and _____ transmit information

A

Dendrites, axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why are pseudounipolar neurons exceptions to the general rule of neurons

A

Single axon that divides, extending one branch/projections into the peripheral tissue (to receive sensory info) and the other branch into the CNS to transmit that info to the spinal cord or brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Neurons communicate via ___

A

Synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What characterizes presynaptic terminals?

A

Numerous vesicles containing neurotransmitters
Mitochondria to provide ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What characterizes postsynpatic contacts?

A

Clustered neurotransmitter receptors & associated proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is glutamate?

A

Major excitatory nt in the CNS
Activation of its glutamatergix synapses makes a neuron MORE likely to fire a signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is GABA?

A

Major inhibitory nt in CNS
Activation of its GABAergic synapses makes a neuron LESS likely to fire a signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 4 steps of vesicle transport?

A

Budding
Movement (diffusion or motor driven)
Tethering
Fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Fusion involves recognitions of the ______ and _____ proteins which interlock and force the donor and acceptor membranes ____
This process allows what to happen?

A

V-SNARE, T-SNARE
Together
Transmembrane receptors are delivered to target membrane and cargo is released into lumen/synaptic cleft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

SNARE dependent fusion of synaptic vesicles and NT release is highly _________

A

Calcium dependent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do neurotoxins from CLostridium botulinum and Clostridium tetani bacteria do to SNARES?

A

Cleave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Fusion of NT vesicles is triggered when ________ in the presynaptic terminal ____, triggering rapid calcium _____

A

Voltage-gated calcium channels, open, influx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Non uniform distribution of ions across membranes results in

A

Voltage potential across membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Glu input relates to EPSP, which is related to graded potential ______

A

Depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

GABA input relates to IPSP which relates to graded potential ____

A

Hyperpolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The axon initial segment (AIS) is highly enriched in ______ that open when membrane voltage goes above a threshold value

A

Voltage gated Na channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the soma of a neuron

A

Cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens if excitatory inputs win?

A

Membrane potential rises above threshold value, triggering opening of voltage gated Na channels at the AIS, result in a large influx of positive ions (first step of action potential)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Related to histology, what is very prominent in neurons? Where specifically ?

A

Cytoskeleton
Axonal and dendritic processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What two cytoskeletal elements are prominent in axons?

A

MT and neurofilaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What process is very active in neurons?

A

Protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are Nissl bodies

A

Concentrations of ribosomes/polysomes in cytosol of neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Where is the axon hillock

A

Adjacent to AIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How are proteins delivered to the axon?

A

Axonal transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Where are most axonal proteins synthesized?

A

In the neuron cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Axonal transport is an energy ______ process and is dependent on _____

A

Dependent
Microtubule MP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does anterograde mean?
What MP controls it?

A

Axonal transport from cell body to axon tip
Kinesin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What does retrograde mean?
What MP controls it?

A

Axonal transport from axon tip to cell body
Dynein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Deficits in axonal transport are implicated in the progression of ?

A

Diabetes, chemotherapy induced neuropathy, Huntington disease, Alzheimer’s disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Mutations in what can casque inherited motor and sensory neuropathies

A

Tubulin, dynein, kinesisns, and specific cargo proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How do viruses and toxins hijack axonal transport system ?

A

Virus travels up nerves via retrograde axonal transport
Enters spinal cord and travels to brain
Viscus disseminates to extra CNS sites via anterograde transport down cranial nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What cells form myelin sheaths?

A

Schwann cells and oligodendrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What percentage of the dry weight of myelin sheath is lipids?

A

70-75%

37
Q

PNS axons are myelinated by ___

A

Schwann cells

38
Q

Myelinations makes action potential conduction _____
Why?

A

Faster
Insulating myelin increases membranes resistance, so membrane depolarization can propagate further along axons without needing to general axon potentials

39
Q

Why cant the entire axon be myelinated ?

A

There’s a limit on how much insulation myelin can provide while still allowing space for enough axons
Membrane potential will still decay over distance within axon

40
Q

What are the gaps in the myelin called?
What do they do?

A

Nodes of Ranvier
Reboost action potential with sodium channels

41
Q

Why does myelination make action potential propagation more efficient?

A

Energy dependent process of action potential generation is only needed at nodes
**saltatory conduction

42
Q

CNS axons are myelinated by ___

A

Oligodendrocytes

43
Q

A single oligodendrocytes can myelinate _____ on multiple separate axons

A

Multiple axon segments

44
Q

What does the oligodendrocyte look like?

A

An octopus!

45
Q

What does a Schwann cell look like?

A

A Swiss roll!

46
Q

Immune mediated demyelinating diseases:

A

Multiple sclerosis (CNS )
Guillain-Barre syndrome (PNS)

47
Q

Inherited demyelinating diseases present with

A

Delayed myelination, dysmyelinatino, demyelination, or a combo
Ex: adrenoleukodystrophy

48
Q

Metabolic demyelinating diseases:
Caused by?

A

Central pontine myelinolysis
Alcoholism/malnutrition

49
Q

Virus induced demyelinating diseases:

A

Progressive multifocal encephalopathy

50
Q

What are the functions of astrocytes? CNS or PNS?

A

Important role in neurovascular coupling (linked to BBB)
Regulation of intercellular fluid comp in brain
Metabolic cooperation with neurons
Regulation of cerebral blood flow

CNS

51
Q

What does the Blood Brain Barrier do?

A

Helps determine the comp of brain interstitial fluid by restricting ionic and fluid movements between blood and brain
Protects the brain from fluctuations in ionic composition that can occur after a meal or exercise

52
Q

What cells are involved in the BBB formation and maintenance?

A

Capillary endothelial cell, astrocytic end feet, astrocyte, tight junction, basal lamina

53
Q

What are the transport functions of the BBB?

A

Paracellular aqueous pathway (water soluble agents)
Transcellular lipophilic pathway (lipid soluble agents)
Transport proteins (glucose, AA, nucleosides, etc)
Receptor mediated transcytosis (insulin, transferrin)
Adoptive transcytosis (albumin, other plasma proteins)

54
Q

____ provide neurons with neurotransmitters and energy

A

Astrocytes

55
Q

Astrocytes mobilize _____ to produce ____
What do neurons do with this product?

A

Glucose, lactate
Convert it to private to generate energy via TCA cycle

56
Q

What do glutamate transporters do?

A

Take up excess glutamate from synaptic cleft and recycle it by converting it to glutamine

57
Q

What are microglia?

A

Major immune cell in CNS
Self renewing tissue macrophage

58
Q

When are microglia activated?
What happens to their shape when they are activated?

A

By physical injury, local inflammation/infection
Rarified to amoeboid (cell body expands, branches less defined)

59
Q

Why do microglia have beneficial and harmful effects in disease?

A

Aid clearance of damaged tissue, also secrete cytokines that can exacerbate inflammation

60
Q

What are ependymal cells?
What are their functions?

A

Line ventricles of brain and central canal of spinal cord
Involved in production and circulation of cerebrospinal fluid (buffer and cushion for brain and spinal cord)

61
Q

Is the ISF_CSF barrier looser or tighter than the BBB?

A

Looser

62
Q

What makes up the spinal cord?

A

White matter, gray matter, spinal ganglion, ventral root

63
Q

What makes up the white matter?

A

Bundles of myelinated axons & oligodendrocytes

64
Q

What makes up gray matter?

A

Collections of neuron cell bodies, Astrocytes

65
Q

What makes up the spinal ganglion?

A

Cell bodies of sensory neurons whose axons project into spinal cord via dorsal root

66
Q

What is the ventral root

A

Projection of motor axons form spinal cord to innervate muscle
**motor neuron cell bodies are in ventral part of spinal cord gray matter

67
Q

In the PNS, neuron cell bodies are clustered together in ____; axons exist in bundles termed ____

A

Ganglia, nerves

68
Q

What are the supporting cells in the PNS?

A

Schwann cells - enshealth nerve fibers & generate myelin
Satellite cells - surround nerve cell bodies & provide trophic support to neurons

69
Q

The epineurium encloses _____

A

The entire nerve

70
Q

The perineurium encloses ___

A

Each fascicle

71
Q

The endoneurium surrounds___

A

Individual nerve fibers

72
Q

What is the endoneurium made of?

A

CT

73
Q

What is the perinerium made of?

A

Concentrically oritented layers of flattened cells surrounded by continuous basement membrane
**blood nerve barrier

74
Q

What is the epinerium made of?

A

Dense irregular connective tissue & adipose tissue

75
Q

Schwann cells can also enshealth multiple _______ PNS axons

A

Nonmyelinated

76
Q

How do PNS axons regenerate after injury?

A

Wallerian degenration of distal axon is triggered by the impaired transport of axon survival factors past the injury site (2/3 days after injury)
Blood nerve barrier breakdown allows influx of macrophages which coooperate with Schwann cells to digest myelin
2 weeks post injury, Schwann a cells dedifferentiate and proliferate and line up to form tubes with basement membrane that guide regenerating axons
Regenerating axons reaches tried and reestablishes synaptic connection

77
Q

How does the myelin react after injury? As seen on histo section

A

Decompaction

78
Q

Is axon regeneration better in CNS or PNS?
Why?

A

PNS
In the CNS, myelin clearance is less efficient; uncleared myelin debris & poor intrinsic growth capacity of adult CNS neurons

79
Q

What brain structure is easily seen in Nissl stains

A

Hippocampus

80
Q

What makes up the brain?

A

Gray matter = neuronal cell bodies & Astrocytes
White matter = axons (myelinated) & oligodendrocytes

81
Q

satellite cells are found in the ___ and support ——

A

PNS, cell bodies

82
Q

schwann cells secrete _____ and are found in the _____

A

neurotrophic factors, PNS

83
Q

astrocytes form _____ and help form the _____
they secrete _____ and take up _____
in the ___

A

support for the CNS, BBB,
neurotrophic factors, K+ neurotransmitters
CNS

84
Q

microglia act as _____ in the ____

A

scavengers , CNS

85
Q

ependymal cells create____ in the ____

A

barriers between compartments , CNS

86
Q

what is multiple sclerosis?

A

CNS demyelinating disease
patient shave increase in antibodies in cerebrospinal fluid and abnormal T cells

87
Q

what is different about the tight junctions in the BBB?

A

resistance significantly higher than other TJ in the body, makes a much tighter barrier to permit much less flow

88
Q

why do astrocytes store glycogen?

A

because the neurons can’t store glucose but they need a lot of it

89
Q

microglia are derived when?

A

embryologically, self renewing **

EXAM 2 - Anatomical Sciences (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions