Neuroscience Exam I

Front 1

somatic and autonomic

Back 1

these are the two divisions of the peripheral nervous system

Front 2

neuron

Back 2

the basic functional component of the nervous system

Front 3

glia

Back 3

the supporting cells of the nervous system; do not participate in synaptic interactions (have no dendrites or axons)

Front 4

neurons

Back 4

the electrical signaling cells of the nervous system

Front 5

synapses

Back 5

interconnection between nerve cells

Front 6

circuits

Back 6

intricate ensembles/groups of neurons

Front 7

afferent

Back 7

these types of neurons are toward the CNS and carry sensory information

Front 8

efferent

Back 8

these types of neurons go away from the CNS toward the periphery and carry motor information

Front 9

interneurons

Back 9

these types of neurons are local circuit neurons

Front 10

nuclei

Back 10

in the CNS, an accumulation of neurons with similar functions and connections; found throughout the brain and spinal cord

Front 11

cortex

Back 11

sheet-like array of nerve cells in the CNS (in the cerebral hemispheres and cerebellum)

Front 12

tracts

Back 12

bundles of axons in the CNS that have glial cells that envelope them

Front 13

gray matter

Back 13

matter in the CNS that is an accumulation of cell bodies

Front 14

white matter

Back 14

matter in the CNS that contains tracts of axons

Front 15

dorsal

Back 15

the sensory information of the body goes in through the __ part of the spinal cord or brainstem

Front 16

ventral

Back 16

the motor information of the body goes out through the __ part of the spinal cord or brainstem

Front 17

astrocytes

Back 17

glial cell in the CNS that have elaborate, star like local processes; they maintain the appropriate chemical environment for electrical signaling

Front 18

oligodendrocytes

Back 18

glial cells in the CNS that lay down a laminated, lipid-rich myelin wrapping that covers some axons and affects the speed of conduction of the AP

Front 19

Schwann cells

Back 19

cells in the PNS that lay down myelin

Front 20

microglia

Back 20

glial cell in the CNS that is derived from hematopoetic stem cells; have properties of macrophages, so they scavenge and remove cellular debris; their concentration increases following brain damage

Front 21

cell body

Back 21

the part of the neuron that contains all the cell organelles, including the nucleus

Front 22

dendrites

Back 22

the part of the neuron that carries information toward the cell body, and is a major site for synapses

Front 23

axon

Back 23

the part of the neuron that conducts signals to the synapse, away from the cell body

Front 24

ganglia

Back 24

in the PNS, local accumulations of nerve cell bodies

Front 25

nerves

Back 25

in the PNS, these are bundles of axons

Front 26

sagittal

Back 26

plane that divides the right and left sides of the body (hemispheres of the brain)

Front 27

frontal/coronal

Back 27

plane of the body that divides it into front and back

Front 28

somatic and autonomic

Back 28

the divisions of the PNS

Front 29

unipolar

Back 29

a neuron that has only one cell process

Front 30

bipolar

Back 30

a neuron that has two extensions, a dendrite and an axon

Front 31

pseudounipolar

Back 31

a type of neuron that has one axon with two processes

Front 32

multipolar

Back 32

a type or neuron that has one axon and many dendrites

Front 33

pyramidal

Back 33

a type of neuron that has a triangular cell body, an axon, and many dendritic processes

Front 34

potential

Back 34

a voltage (charge difference) across a barrier (i.e. the membrane)

Front 35

resting potential

Back 35

voltage across the membrane while the neuron is at rest

Front 36

action potential

Back 36

the stereotyped pattern of voltage changes across the membrane while the neuron is sending an electrical signal to its target

Front 37

electrochemical equilibrium

Back 37

the point of exact balance between the concentration gradient and the electrical gradient

Front 38

Nernst

Back 38

equation used to give the electrochemical equilibrium for a certain ion

Front 39

K

Back 39

at rest, neurons at permeable primarily to what ion?

Front 40

Purkinje

Back 40

neurons that are responsible for motor coordination output from the brain

Front 41

capacitative current

Back 41

the spreading of charge change across the membrane

Front 42

refractory period

Back 42

time in which a sodium channel is inactivated so the axon can propagate the action potential in just one direction

Front 43

myelin

Back 43

this material is responsible for insulating the axons to prevent charge loss, for increasing the velocity of conduction of the AP along the axons

Front 44

synapse

Back 44

a point of contact between a neuron and a target cell that allows for cell to cell communication

Front 45

Acetylcholine

Back 45

neurotransmitter that functions in neuromuscular transmission

Front 46

glutamate

Back 46

neurotransmitter that excites postsynaptic neurons in the human CNS

Front 47

GABA and glycine

Back 47

neurotransmitters that inhibit post-synaptic neurons in the human CNS

Front 48

dopamine

Back 48

neurotransmitter that functions in motivation and reward behaviors

Front 49

seratonin

Back 49

neurotransmitter that functions in emotion

Front 50

critical periods

Back 50

times of greatest change during development (there is an ideal window of time to acquire a function after which this is no longer possible)

Front 51

gastrulation

Back 51

the invagination of the developing embryo; starts as a single sheet of cells and the invagination produces 3 germ layers

Front 52

ectoderm

Back 52

the outermost germ layer

Front 53

mesoderm

Back 53

the middle germ layer

Front 54

endoderm

Back 54

the innermost germ layer

Front 55

mesoderm

Back 55

this layer gives rise to the notochord

Front 56

notochord

Back 56

this structure develops during gastrulation and extends along the midline of the embryo from anterior to posterior; it specifies the topography of the embryo and determines the position of the nervous system; it sends inductive signals to the overlying ectoderm to begin neurulation

Front 57

neurulation

Back 57

the differentiation of the neuroectoderm into neural precursor cells

Front 58

neural plate

Back 58

formed from the midline ectoderm that thickens into a distinct columnar epithelium upon signaling from the notochord

Front 59

neural tube

Back 59

formed from the infolding of the lateral margins of the neural plate

Front 60

neural tube

Back 60

this embryonic structure gives rise to the brian and spinal cord

Front 61

neural groove

Back 61

the precursor of the neural tube that is formed by folding of the neural plate

Front 62

somites

Back 62

masses of mesoderm distributed along the sides of the neural tube that eventually become skin, skeletal muscle, and vertebrae

Front 63

floorplate

Back 63

a special strip of epithelial-like cells in proximity to the notochord at the ventral midline of the neural tube; it elaborates signaling molecules to tell adjacent cells what they;re going to do; it determines the dorso-ventral polarity of the neural tube and differentiation of the neural precursor cells that lead to spinal and brainstem motor neurons

Front 64

neural crest cells

Back 64

transient, multipotent, migratory cell population during neurulation that migrate away from the neural tube through mesenchymal cells and form a variety of different things, including: the PNS, adrenal gland, enteric NS, and pigment cells, cartilage, and bone

Front 65

inducing signals

Back 65

molecules that modulate gene expression (derived from the notochord and the roof and floor plates); cause changes in shape, motility, and gene expression in target cells

Front 66

retinoic acid

Back 66

molecule that is a derivative of vitamin A; it is a member of the steroid/thyroid family of hormones and it activates transcription factors through retinoid receptors

Front 67

peptide hormones

Back 67

signaling molecules transcribed from the genome, including fibroblast growth factor, transforming growth factor, and sonic hedgehog

Front 68

sonic hedgehog (Shh)

Back 68

this inductive signal is essential for differentiation of motor neurons in the ventral spinal cord (comes from the floorplate)

Front 69

Transforming growth factor (TGF)

Back 69

this inductive signal is important for the specification of the neural plate with subsequent differentiation of the dorsal part of the spinal cord and the hindbrain (comes from the roofplate)

Front 70

spina bifida

Back 70

failure of the posterior neural tube to close completely

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anencephaly

Back 71

failure of the anterior neural tube to close completely

Front 72

partitioning

Back 72

the formation of major brain subdivisions during embryonic development

Front 73

prosencephalon

Back 73

gives rise to the forebrain during partitioning

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mesencephalon

Back 74

gives rise to the midbrain during partitioning

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rhombencephalon

Back 75

gives rise to the hindbrain during partitioning

Front 76

telencephalon

Back 76

this structure forms from the lateral aspects of the rostral prosencephalon; eventually forms the cerebral cortex, hippocampus, ganglia, and olfactory bulb

Front 77

diencephalon

Back 77

this structure forms from the caudal portion of the prosencephalon, and eventually becomes the thalamus, hypothalamus, and the retina

Front 78

dorsal mesencephalon

Back 78

this portion of the brain gives rise to the tectum

Front 79

ventral mesencephalon

Back 79

this portion of the brain gives rise to the tegmentum, a collection of nuclei

Front 80

metencephalon

Back 80

this structure forms from the rostral rhombencephalon, and eventually becomes the cerebellum and the pons

Front 81

myelencephalon

Back 81

structure that comes from the caudal part of the rhombencephalon, that eventually forms the medulla

Front 82

hydrocephalus

Back 82

genetic abnormality that is caused from enlarged ventricles; mutations of genes on X chromosomes, deficits in cell adhesion, or blockage of CSF circulation

Front 83

Fragile X syndrome

Back 83

disease with triplet repeats in a subset of genes on the X chromosome, deficit in dendritic process and synapse stabilization; can cause mental retardation

Front 84

trisomy 21

Back 84

abnormality with triplet 21st chromosomes, so an abundance of genes; there are increased levels of signaling molecules, meaning altered neural development

Front 85

growth cone

Back 85

a dynamic, actin supported extension of a developing axon seeking its target; situated on the very tips of axons and dendrites,

Front 86

lamellapodium

Back 86

a cytoskeletal actin motor which pulls the cell forward during the process of cell migration

Front 87

filapodia

Back 87

projections of the cell that form local adhesions with substratum, linking it to the cell surface; rich in receptors and cell adhesion molecules

Front 88

chemotrophic factors

Back 88

factors that are essential for cell survival; nourish cells to they can perform growth that is guided by neurotropic factors

Front 89

chemotropic factors

Back 89

factors that cause movement by chemical stimulus in organisms; they guide the cell to where they need to go

Front 90

cell adhesion molecules (CAMs)

Back 90

these tropic factors bind the cells to substrates in the ECM

Front 91

netrin

Back 91

a substance present in the floor plate that encourages commissural axon outgrowth; therefore, without netrin, there would be no cell processes

Front 92

semaphorin

Back 92

protein that acts as an axonal growth cone guidance molecules; primarily act to steer axons away from inappropriate areas

Front 93

meninges

Back 93

the three protective tissue layers around the brain and spinal cord

Front 94

dura mater

Back 94

the outermost, thick and touch meninges

Front 95

arachnoid mater

Back 95

the middle meninges; there are cisterns where there are larger spaces, and major vessels run through this space

Front 96

subarachnoid space

Back 96

the space under the arachnoid mater that houses the CSF

Front 97

pia mater

Back 97

the innermost, thin and delicate meninges

Front 98

cerebrospinal fluid

Back 98

a fluid that bathes the brain and spinal cord; it is found in the subarachnoid space and contains very little protein and ion concentrations that are different from plasma

Front 99

choroid plexus

Back 99

forms the cerebrospinal fluid

Front 100

ventricles

Back 100

series of interconnected, fluid-filled spaces in the forebrain and the brainstem

Front 101

lateral ventricles

Back 101

these ventricles are the largest in each of the cerebral hemispheres

Front 102

third

Back 102

this ventricle is a narrow midline space between the right and left thalamus

Front 103

cerebral aqueduct

Back 103

this ventricle goes through the midbrain

Front 104

fourth

Back 104

this ventricle is a larger space in the dorsal pons and the medulla (located in the mesencephalon)

Front 105

arachnoid villi

Back 105

these projections into the subarachnoid space resorb CSF back into the bloodstream

Front 106

hydrocephalus

Back 106

a disease that occurs when there is a physical blockage of the circulation of CSF; causes a huge increase in intercranial pressure

Front 107

blood brain barrier

Back 107

this is the barrier formed by specialized endothelial cells that overlap and form tight junctions; it functions to maintain a constant intercerebral environment, and protects the brain from rapid changes in ion concentrations

Front 108

perivascular edema

Back 108

this is an accumulation of fluids from the blood vessels of the brain when there is disruption of the blood brain barrier

Front 109

venous sinuses

Back 109

these structures drain blood from the brain into the internal jugular vein; are located between the two layers of dura

Front 110

endosteal and meningeal

Back 110

the two layers of the dura

Front 111

superior sagittal

Back 111

this sinus runs in the interhemispheric fissue formed at the upper margin of the falx cerebri

Front 112

falx cerebri

Back 112

an arched fold of dura mater that extends vertically between the cerebral hemispheres in the longitudinal fissues

Front 113

inferior sagittal

Back 113

this sinus is formed by the lower free edge of the falx cerebri and arches over the corpus callosum; it ends in the great cerebral vein of Galen, then forms the straight sinus

Front 114

straight sinus

Back 114

this sinus is formed by the union of the inferior sagittal sinus with the great vein; it becomes continuous with the transverse sinuses

Front 115

transverse

Back 115

this sinus passes laterally from the confluence of the sinuses into the attached border of the tentorium cerebelli

Front 116

tentorium cerebelli

Back 116

an extension of the dura mater that separates the cerebellum from the inferior portion of the occipital lobes

Front 117

sigmoid sinus

Back 117

these bilateral sinuses follow an s-shaped course in the posterior cranial fossa, then turn to enter the jugular veins; they drain the blood out of the cranium

Front 118

confluence

Back 118

this area is where five different sinuses come together at the end of the superior sagittal sinus; the sinuses that communicate here are the superior sagittal, transverse (2) and the occipital

Front 119

vertebral and internal carotid

Back 119

the two main branches of the dorsal aorta

Front 120

vertebral artery

Back 120

this artery arises from the subclavian arteries and supplies the entire posterior fossa, occipital lobes, portions of the temporal lobes, brainstem, and cerebellum

Front 121

foramen magnum

Back 121

this is where the vertebral artery enters the cranium

Front 122

internal carotid

Back 122

this artery comes from the common carotid artery, and supplies the cerebral hemispheres

Front 123

carotid canal

Back 123

this is where the internal carotid artery enters the cranium

Front 124

anterior spinal artery

Back 124

a branch of the vertebral arteries that supplies the medulla and the anterior spinal cord

Front 125

posterior spinal arteries

Back 125

there are two of these arteries that branch from the bilateral vertebral arteries; they run along the posterior spinal cord and supply the dorsal columns and dorsal horns (Sensory regions)

Front 126

posterior inferior cerebellar artery

Back 126

this is a branch of the vertebral artery that supplies the medulla and the cerebellum

Front 127

basilar

Back 127

this artery is formed by the coming together of the anterior spinal, posterior spinal, and PICA arteries

Front 128

anterior inferior cerebellar artery

Back 128

this bilateral artery branches off the basilar artery and supplies the lateral pons and the anterior-inferior cerebellum

Front 129

superior cerebellar artery

Back 129

this bilateral artery branches off the basilar artery and supplies the lateral midbrain and the superior/lateral cerebellum

Front 130

posterior cerebral artery

Back 130

this bilateral artery branches from the basilar artery and supplies the occipital lobe, inferior and medial temporal lobe (hippocampus), and the posterior corpus callosum

Front 131

thalamoperforant and thalamogenulate

Back 131

branches of the posterior cerebral artery that branch off and supply the thalamus, subthalamus, oculomotor nuclei, cerebral peduncle, and other midbrain structures

Front 132

anterior cerebral artery

Back 132

bilateral artery that branches from the internal carotid artery that supplies the inferior frontal lobe, the medial surface of the frontal and parietal lobes, the anterior corpus callosum, the deeper cerebrum, limbic structures, the head of the caudate (basal ganglia) and the anterior limb of the internal capsule); located in the innermost border between the cerebral hemispheres

Front 133

middle cerebral artery

Back 133

this bilateral artery is a branch from the internal carotid; it has large branches that supply most of the lateral cortex and white matter of the hemisphere's convexity; it supplies that lateral inferior frontal lobe including Broca's area, parietal lobe with the sensory cortex, superior temporal lobe (Wenicke's area), some of the occipital lobe and insula, and the deeper cerebrum (putamen, body of caudate)

Front 134

posterior communicating

Back 134

these bilateral arteries connect the posterior cerebral arteries to the internal carotid artery

Front 135

anterior communicating artery

Back 135

this artery connects the two anterior cerebral arteries

Front 136

circle of willis

Back 136

this structure is a composition of the posterior cerebral arteries, the posterior communicating arteries, the internal carotids, the anterior cerebral arteries, and the anterior communicating artery; it provides an overlapping blood supply and creates redundancies so that if one part were blocked, blood from other parts of the structure could preserve the brain well enough to avoid ischemia

Front 137

ischemic

Back 137

this type of stroke is due to an insufficiency of blood supply from an occlusive block or closure; it also results in a reduction of glucose and oxygen and is reversible, depending on the severity and duration

Front 138

anoxia

Back 138

reduced oxygen

Front 139

hemorrhagic

Back 139

this type of stroke is due to bleeding from a vessel, and can occur at the surface or deep

Front 140

anterior cerebral

Back 140

a more distal occlusion of this artery causes sensory and motor deficits on the opposite foot and leg and mild sensory loss; paresis of the contralateral arm, personality changes, akinetic mutism, gait apraxia, and ataxia

Front 141

middle cerebral

Back 141

total occlusion of this artery causes contralateral hemiplegia, hemianesthesia, head and eyes deviating, global aphasia, and neglect of the contralateral side of the body

Front 142

posterior cerebral

Back 142

occlusion of this artery causes head and eyes to deviate away from lesion, visual hallucinations, and memory loss; pain and sensory loss (thalamus), the subthalamus

Front 143

Weber's syndrome

Back 143

a syndrome associated with blockage of the posterior cerebral artery that causes oculomotor palsy with contralateral hemiplegia that results from damage to the oculomotor nucleus and cerebral peduncle

Front 144

basilar artery

Back 144

a complete blockage of this artery is REALLY bad; will cause bilateral sensory and motor deficits due to interruption of the sensory and motor pathways with variable cerebellar and cranial nerve findings; the person often becomes comatose due to ischemia of the midbrain reticular activating system

Front 145

locked in syndrome

Back 145

syndrome that results from a blockage of the basilar artery when there is interruption of the motor pathways but a sparing of the reticular activating system; person presents with quadriplegia and mute but consciousness

Front 146

reticular activating system

Back 146

a system in the body that is responsible for regulating the sleep-wake cycle and for moderating alertness; it is composed of several neuronal pathways connecting the brainstem to the cortex

Front 147

cerebellar

Back 147

occlusion of these arteries typically causes nausea and vomiting, dizziness, gait ataxia, and sometimes limb ataxia

Front 148

wallenberg's

Back 148

a syndrome that occurs with blockage of the cerebellar arteries that can be due to infarct in the PICA distribution, causing ipsilateral ataxia, nausea and vomiting, slurred speech, loss of pain and temperature feeling on contralateral side of the body

Front 149

neuromuscular junction

Back 149

this is a chemical synapse between a motor neuron and a skeletal muscle fiber; it includes the motor neuron, the muscle fiber, and the Schwann cell processes

Front 150

alpha motor neuron

Back 150

this is the neuron that exits the ventral root of the spinal cord and travels via the peripheral nerve to the muscle; it branches to terminate on multiple muscle fibers; at the muscle fiber, it splits into several unmyelinated branches

Front 151

boutons

Back 151

presynaptic terminals at the end of axon branches; they contain synaptic vesicles that contain ACh and mitochondria for energy for vesicle recycling

Front 152

active zones

Back 152

these areas of the membrane are specialized for vesicular release of ACh; it contains voltage gated calcium channels that permit calcium to enter the terminal in response to a presynaptic action potential

Front 153

Schwann

Back 153

these cells cap the nerve boutons and insulate them from the environment; provide protection; they contact preterminal portion of the neuron and form a myelin sheath and increase the impulse spread of the neuron

Front 154

motor unit

Back 154

an alpha motor neuron plus all the muscle fibers it innervates

Front 155

motor pool

Back 155

this is a set of all the alpha motor neurons contributing to the innervation of an entire muscle

Front 156

motor end plate

Back 156

this is the specific area where the alpha motor neuron innervates the muscle fiber , which is the flattened end of a motor neuron that transmits impulses to the muscle

Front 157

junctional folds

Back 157

folds in the postsynaptic membrane (muscle) that align with active zones on the presynaptic terminal (boutons); they are the site of post-synaptic ACh receptors and voltage gates sodium channels

Front 158

synaptic cleft

Back 158

the space between the boutons and the muscle membrane; about 100 mm thick

Front 159

basement membrane/basal lamina

Back 159

this membrane aligns the junctional folds with the active zones; it contains collagen and glycoproteins and releases AChE

Front 160

SNAPs

Back 160

these proteins prime the vesicles filled with ACh for fusion with the presynaptic membrane by regulating the assembly of SNARE proteins

Front 161

SNARE proteins

Back 161

proteins that attach the vesicle to the presynaptic membrane; they are contained both on the vesicle and the presynaptic plasma membrane

Front 162

synaptotagmin

Back 162

found in the vesicle membrane; it binds calcium that signals a conformational change and makes it more receptive to the SNARE protein syntaxin that is located on the presynaptic plasma membrane

Front 163

acetylcholinesterase (AChE)

Back 163

this enzyme hydrolyzes ACh intro acetic acid and choline; it is concentrated in the synaptic cleft after being made by the basal lamina

Front 164

safety factor

Back 164

this factor acts as a buffer that produces an end plate potential that is well above the needed threshold for an action potential to occur; therefore, the presynaptic action potential GUARANTEES that there will be a postsynaptic action potential in the muscle, due to the large number of vesicles being released with each action potential

Front 165

synapsin

Back 165

this protein regulates the amount of synaptic vesicles that are available for release via exocytosis; during the action potential, they are phosphorylated and allow the vesicles to migrate to the presynaptic membrane and release the neurotransmitter

Front 166

excitatory

Back 166

the potentials in the NMJ are only __ in nature

Front 167

myasthenia gravis

Back 167

this is an autoimmune disorder that reduces the number of functional ACh receptors and can eventually destroy them, diminishing the efficacy of synaptic transmission; the symptoms include weak eye muscles, dropping of eyelids, blurred vision, difficulty swallowing and slurred speech, and weakness in distal muscles

Front 168

Botulism

Back 168

this neurotoxin prevents presynaptic ACh release by cleaving the SNARE proteins; it manifests as symmetric, progressive, descending flaccid paralysis in the arms, leg, trunk, and respiratory musculature; death occurs due to respiratory failure in 3-5% of cases; symptoms include blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, and muscle weakness

Front 169

Lambert Eaton

Back 169

this syndrome targets calcium channels at the presynaptic terminal and reduces the release of ACh; it is usually associated with certain cancers; blood usually has a high concentration of antibodies for calcium channel proteins and symptoms include progressive muscle weakness

Front 170

tetanus

Back 170

this disease is caused by a bacteria that infects wounds, and it works by cleaving synaptobrevin, a SNARE protein

Front 171

black widow venom

Back 171

this toxin causes a mass exodus of ACh, exhausts the supply, and does not allow for recycling; manifests through paralysis

Front 172

curare

Back 172

this toxin competes for ACh receptors by binding to them so ACh can't

Front 173

motor unit

Back 173

this is the functional unit of movement; it is composed of the alpha motor neuron and the fibers it innervates

Front 174

innervation ratio

Back 174

this is the ratio of the alpha motor neuron to the number of fibers it innervates

Front 175

motor pool

Back 175

this is all of the motor neurons innervating a particular muscle; a muscle is innervated by many motor axons from different neurons

Front 176

small

Back 176

these size motor units have small, red, slow fatiguing fibers and have low force, sustained contraction, and low fatigue

Front 177

large

Back 177

these size motor units have large, white, fast fatiguing fibers with high force and brief exertions, and also moderate force and resistant to fatigue fibers

Front 178

sag

Back 178

the decline in force after the initial increase in tension during unfused tetanus; exhibited in fast but not slow fibers, showing that slow fibers can sustain their force over a longer period of time

Front 179

rate coding

Back 179

this occurs when force output is modulated by a firing rate

Front 180

hyperpolarization

Back 180

making the membrane potential more negative

Front 181

depolarization

Back 181

making the membrane potential more positive

Front 182

passive current flow

Back 182

current conduction b neurons in the absence of action potentials

Front 183

conduction velocity

Back 183

the action potential's measurable rate of transmission

Front 184

nodes of Ranvier

Back 184

the places along an axon where the actual action potential is generated and where the voltage gated Na channels are located

Front 185

microscopic

Back 185

the currents that are flowing through single ion channels

Front 186

macroscopic

Back 186

the currents that are flowing through a large number of channels that are distributed over an extensive region of surface membrane

Front 187

active transporters

Back 187

transmembrane proteins that store up energy in the form of ion concentration gradients that translocate ions against their electrochemical gradients through the consumption of energy

Front 188

ATPase

Back 188

an active transporter that acquires energy directly from the hydrolysis of ATP

Front 189

ion exchangers

Back 189

active transporters that generate their energy from the electrochemical gradients of other ions

Front 190

electrogenic

Back 190

pumps that can generate an electrical current that hyperpolarize the membrane potential

Front 191

electrical

Back 191

these types of synapses allow ionic current to flow passively through the gap junction pores from one neuron to another; usual source of this current is the potential difference by the action potential

Front 192

cotransmitters

Back 192

when more than one transmitter is present within a nerve terminal, they are called __

Front 193

end plate potential

Back 193

the change in membrane potential of the postsynaptic muscle fiber following an action potential in the presynaptic motor neuron

Front 194

mini EPPs

Back 194

spontaneous changes in muscle cell membrane potential that occur even the absence of stimulation of the presynaptic motor neuron

Front 195

synapsin

Back 195

this protein links vesicles to actin filaments in the cytoskeleton to keep them tethered in the reserve pool of the presynaptic terminal

Front 196

postsynaptic potential

Back 196

the postsynaptic membrane potential change that occurs when the neurotransmitter binds to the postsynaptic cell

Front 197

excitatory

Back 197

this postsynaptic potential will increase the likelihood of a postsynaptic action potential occurring; will depolarize the membrane

Front 198

inhibitory

Back 198

this postsynaptic potential will decrease the likelihood of a postsynaptic action potential occurring; will hyperpolarize the membrane

Front 199

summation

Back 199

whether the different inputs results in the production of an action potential or not depends on the balance between excitation and inhibition

Front 200

ionotropic

Back 200

receptors that are linked directly to ion channels; aka ligand gated because they combine neurotransmitter binding and channel functions into a single molecular entity

Front 201

metabotropic

Back 201

a type of receptors that are called this because the eventual movement of ions through a channel depends on one or more metabolic steps; aka G protein receptors; the NT binds to the receptor which then activates G proteins, which dissociates and then binds to other proteins to make messengers that open or close ion channels

Front 202

neuropeptides

Back 202

these types of neurotransmitters are relatively large composed of 3 to 36 amino acids

Front 203

nicotinic

Back 203

the type of receptor that accepts ACh at the postsynaptic terminal

Front 204

biogenic amine

Back 204

these transmitters regulate many brain functions; made up of the three catecholamines (dopamine, norepinephrine, and epinephrine) and histamine and serotonin

Front 205

gastrulation

Back 205

the local invagination of the subset of cells in the developing embryo; forms the three primitive cell layers; defines the midline,anterior-posterior, and dorsal-ventral axes

Front 206

notochord

Back 206

formation of this structure during gastrulation is essential for the subsequent development of the nervous system; comes to define the embryonic midline and thus the axis of symmetry of the entire body

Front 207

primitive streak

Back 207

the surface indentation that eventually forms the notochord

Front 208

neuroectoderm

Back 208

the ectoderm that lies immediately above the notochord that eventually becomes the entire nervous system

Front 209

neurulation

Back 209

the process of causing neuroectodermal cells to differentiate into neural precursor cells

Front 210

neural plate

Back 210

the layer of the midline ectoderm that forms into a distinct columnar epithelium

Front 211

neural tube

Back 211

a folding of the neural plate causes the formation of this stricture, which goes on to form the brain and spinal cord

Front 212

neural crest

Back 212

these cells follow specific pathways where they are exposed to specific inductive signals that influence their differentiation; give rise to glia of autonomic ganglia, adrenal gland, and enteric nervous system