Brainscape's Knowledge GenomeTM

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


See full index

BIOL1191 > Chapter 12 - Nervous System > Flashcards

Chapter 12 - Nervous System Flashcards

1
Q

Neuroglial Cells

A
  • AKA “Nerve Glue Cells”
  • Small + numerous
  • Capable of mitosis
  • 6 Types Total (4 in CNS, 2 in PNS)
  • Gliomas = Brain Cancer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Neuropeptides (4 Main Examples)

A
  1. Opiate Peptides
  2. Substance P
  3. Hypothalamic releasing & release inhibiting hormones
  4. Cholecystokinin-Pancreozymin (AKA “CCK-PZ” or “CCK”)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Microglia

A

Microgilal Cells

-Phagocytic cells that are found on CNS injury sites

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

Distribution of Different Ion Species

A 
Na+ = Main extracellular cation
Cl- = Main extracellular anion
K+ = Main intracellular cation
A= Polyvalent anion "A" (Intracellular fixed anions, e.g., carboxyl groups of proteins)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 Parts of the Neuron

A
  1. Dendrite
    2 .Axon
  2. Cell Body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Subcellular Locations of Voltage-gated Channels

A

Always located in places 2/ action potentials:

  • Axons of motor neurons, interneurons, bipolar & unipolar sensory neurons
  • Sarcolemmas of skeletal muscle cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Biogenic Amines (3 Main Examples)

A
  1. Noradrenaline
  2. Dopamine
  3. Serotonin
    * Can be either excitatory or inhibitory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Interneurons

A

Interneurons = 90% of all neurons

  • Only found in CNS
  • Conduct nerve impulses between different parts of CNS
  • AKA “Association Neurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Absolute Refractory Period

A
  • Period during which nerve/muscle cell cannot generate another AP, even w/ a strong stimulus
  • Caused by open/inactive Na+ channels (Not yet returned to resting state)
  • Large diameter fibers: short absolute refractory period
  • Small diameter fibers: long absolute refractory period
  • Refractoriness = one-way transmission of AP; direction of AP propagation always away from membrane areas which have just fired
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3 Steps During Action Potentials

A
  1. Receptor Binding
  2. Depolarization
  3. Repolarization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Differences in Plasma Membrane Permeability to Ions

A

Resting Membrane is 50-100x more permeable to K+ than to Na+, so RMP will be near K+ equilibrium potential (-90 mV)
-Defined as membrane potential that just balances K+ outflow

*RMP = -70 mV, so slightly leaky to Na+

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

Temperature

A

A low temperature rate will lower AP conduction rate. and sometimes even block conduction

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

Action Potential (AKA “Nerve Impulse”)

A

Action Potential = Moving transient electrical polarity reversal; moves from one end of neuronal fiber to the other

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

Synaptic Cleft

A

Small gap between 2 chemical synapses

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

Nitric Oxide

A
  • Is both a neurotransmitter & hormone
  • “Endothelium-derived relaxation factor” (EDRF)
  • Made by MP Synthetase from arginine
  • Very brief activity
  • Very dangerous free radical
  • NO -> Guanyl cyclase activation -> cyclic-GMP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Agonist

A
  • Agents which enhance synaptic transmission (e.g., metoclopramine; releases ACh)
  • Agents which mimic the effects of a hormone/neurotransmitter, showing both affinity for receptor & efficacy (e.g., salbutamol; helps bronchodilation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

3 PNS Subdivisions

A
  1. Somatic Nervous System (SNS)
  2. Autonomic Nervous System (ANS)
  3. Enteric Nervous System (ENS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Opiate Peptides

A
  • Endorphins, enkephalins & dynorphins are all examples of Opiate Peptides
  • Inhibit pain by blocking substance P
  • Aid in learning & memory
  • Regulate mood, body temperature & sex drive
  • Associated w/ schizophrenia & depression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

2 Tract Types

A
  1. Myelinated = CNS white matter
  2. Unmyelinated (+ Neuron cell bodies, dendrites & neuroglia) = CNS gray matter
    - “H-shaped” in spinal cord
    - Outer covering of cerebral & cerebellar hemispheres in brain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Relative Refractory Period

A
  • Period during which nerve/muscle cell can generate another AP, but only w/ a supra-threshold stimulus
  • Caused by Na+ channels being in resting state, but K+ channels still being open
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

2 Features Affecting Nerve Impulses

A
  1. Resting Membrane Potential = Electrical charge separation across lipid bilayer
  2. Presence of ion channels in membrane = Path for ion movement in electrical current, leading to change of membrane potential (Can be gated or ungated)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

3 Factors Affecting Graded Potentials

A
  1. # of Opened Channels
  2. Duration
  3. Channel type - excitatory or inhibitory
    - Mechanically-gated = usually excitatory
    - Ligand-gated w/ ACh ligand = usually excitatory
    - Ligand-gated w/ glycine ligand = usually inhibitory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Oligodendrocytes

A

Oligodendrocytes

  • Form myelin sheaths around CNS fibers, however do NOT form a neurolemmal sheath
  • One oligodendrocyte myelinates many fibers
  • CNS fibers cannot regenerate
  • Demyelination occurs in some disease conditions (e.g. Tay-Sachs disease)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Suprathreshold Graded Potential

A

Firing of a series of action potentials, only stopping when electrical potential falls bellow -55mV

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

Hyperkinesis

A

Excessive dopamine levels; caused by Huntington’s Disease

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

Astrocytes

A

Astrocytes

  • Can be protoplasmic or fibrous
  • Cytoplasmic processes that support neurons + capillaries
  • Participate in the “blood-brain barrier” by regulating cerebral capillary permeability
  • Homeostasis of K+ in ECF
  • Terminate neurotransmitter action by glial uptake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Neurotransmitters

A
  • Chemical messengers that transmit signals across chemical synapses
  • Can be either excitatory or inhibitory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

2 ANS Subdivisions

A
  1. Sympathetic Division = Used for energy expending “fight or flight” activities
  2. Parasympathetic Division = Used for energy conserving/ restoring “vegetative” activities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Intracellular Ion Movement

A

Most intracellular anions simply cannot leave the cell

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

Central Nervous System

A

CNS = Brain + Spinal Cord; integrates sensory info, motor commands to muscles + glands, processes thoughts, memories + emotions

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

3 Mechanisms of Neurotransmitter Termination

A
  1. Diffusion from cleft
  2. Enzymatic degradation
  3. Re-uptake into neurons (uptake 1) and uptake into glial cells (uptake 2) by neurotransmitter transportrers
    * SSRIs block re-uptake of serotinin, which leads to serotonin buildup in cleft
    * MAO inhibitors block intraneuronal neurotransmitter breakdown
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

3 Functional Classifications of Neurons

A
  1. Motor Neurons
  2. Sensory Neurons
  3. Interneurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Additional Axonal Features

A

Axon Collaterals = Side branches
Axon Terminals
-Have synaptic end-bulbs + varicosites, containing synaptic vesicles filled w/ neurotransmitters
-Slow Axonal Transport = Movement of axoplasm
-Fast Axonal Transport = Movement of substances (e.g., organelles, debris) along microtubules between cell body + synaptic end-bulbs/ synaptic varicosities
-Kinesins = Microtubule-dependent carrier ATPases

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

Parallel After-discharge Circuits

A

-Generate many APs in quick succession

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

Myelination

A
  • Unmyelinated fibers undergo continuous conduction; the slow, sequential depolarization of each adjacent membrane area
  • Myelinated fibers undergo saltatory conduction; ion currents flow through axoplasm & extracellular fluid, basically “leap” from one Node of Ranvier to the other (much faster)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Tracts

A

Bundles of neuronal fibers within CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Ganglia

A

Clusters of PNS neuron cell nodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Motor Neurons

A

Motor Neurons = Always mulit-polar

  • Starts from CNS to various types of effectors
  • Smooth + cardiac muscle (involuntary)
  • Skeletal muscle (voluntary)
  • Glands
  • “Innervation” of above structures allows muscle contractions/ gland secretions
  • AKA “Efferent Neurons”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Mechanically-gated Channels

A

-Open/close in response to vibration, touch, pressure or sheer (e.g., hearing, balance, or touch)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Satellite Cells

A

Satellite Cells

-Responsible for supporting PNS nerve ganglia + regulating exchange between interstitial fluid + neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Neurotransmitter Co-localization

A

When neurons may contain more than one neurotransmitter type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

GABA

A
  • Inhibitory neurotransmitter in CNS
  • Used by 1/3 of brain synapses
  • Opens GABA-gated Cl- channels, creating IPSPs
  • Ativan has same effect
  • Reduces anxiety + relaxes skeletal muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Sensory Receptors

A
  • Specialized endings sensitive to stimuli; are either free dendrites/ non-neuronal structures associated w/ dendrites
  • Transduce sensations
  • Stimulation causes nerve impulse to travel along sensory neuron to CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Fiber Diameter

A
  • A Fibers: Up to 20 nanometers in diameter & myelinated, conduction speeds of up to 130 m/sec, found in SNS sensory & motor fibers, rapid input & response
  • B Fibers: 2-3 nanometers in diameter & myelinated, conduction speeds of up to 15 m/sec, found in ANS sensory & motor neurons in viscera
  • C Fibers: 1 nanometer diameter & unmyelinated, conduction speeds of only 2 m/sec, found in ANS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Resting Membrane Potential (RMP)

A

RMP = Voltage drop measurable across neuronal fiber membrane when cell isn’t conducting a nerve impulse

  • Results from differences in electrical charges located on either side of the membrane (polarization)
  • Outside = (+Charge), Inside = (-Charge)
  • Average neuronal RMP = -70 mV
  • Non-neuronal cells: +5 to -100 mV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

2 Types of PNS Neuroglia

A
  1. Schwann Cells

2. Satellite Cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Repolarization

A

Repolarization, caused by closing of Na+ channels and K+ outflow from opening of voltage-gated K+ channels (Actually causes hyperpolarization to -85 mV)
*Approx. 20,000 K+ ions flow outward

48
Q

Trigger Zone Threshold

A
  • 55 mV has to be reached in order for an action potential to fire
  • If threshold isn’t reached, the potential dies away
49
Q

Nuclei

A

Clusters of CNS neuron cell bodies

50
Q

2 Types of Ion Channels

A
  1. Leaky (non-gated) channels
    - randomly alternates between open & closed
    - explains high K+ permeability of resting neuron
  2. Gated channels
    - Open in response to specific stimuli
    - 3 different subtypes
51
Q

4 Drugs that Modify Synaptic Transmission

A
  1. L-dopa (Parkinson’s Disease)
  2. Amphetamines (Depression & obesity)
  3. Botulinum Toxin (NMJ Blockade)
  4. Cocaine
52
Q

CCK-PZ

A
  • Regulates satiety

- Also responsible for gall bladder contraction , bile & pancreatic enzyme secretion

53
Q

Peripheral Nervous System

A

PNS = Cranial + Spinal Nerves (w/ all branching nerves); carries info into + out of CNS. Has 3 Subdivisions

54
Q

7 Neurotransmitter Examples

A
  1. Acetylcholine
  2. Amino Acids
  3. Biogenic Amines
  4. Purines
  5. Nitric Oxide
  6. Carbon Monoxide
  7. Neuropeptides
55
Q

Na+/K+ -ATPase Pump

A

Restores resting state of nerve cell by pumping 2 K+ ions in for every 3 Na+ ions pumped out

56
Q

Autonomic Nervous System

A

Autonomic Nervous System (ANS)

  • Sensory neurons from viscera to CNS
  • Motor neurons from CNS to smooth + cardiac muscles + glands
  • Involuntary
  • Has 2 more subdivisions
57
Q

Neurolemmal Sheaths

A
  • AKA “Sheath of Schwann” (Part of Schwann Cell containing cytoplasm + nuclei)
  • May cover unmyelinated fibers
  • Also cover myelinated fibers (outside myelin sheath)
  • Neurolemma only around PNS fibers
  • Nissl body chromatolysis = When the neurolemmas of axon’s many Schwann cells form a regeneration tube that guides/stimulates regrowth of axon (Role of Neurolemmal Sheath during Wallerian Degeneration)
58
Q

Electrical Synapses

A
  • Current flows between cells through gap junctions (connexons)
  • Fast communication
  • Able to synchronize activity of a group of cells (e.g., heart, “functional syncytium”)
59
Q

Acetylcholine

A
  • Found in both the CNS & PNS
  • Can be Excitatory or Inhibitory
  • Excitatory at NMJ
  • Inhibitory at vagal synapses w/ heart
  • Action terminated by acetylcholinesterase
60
Q

Converging Circuits

A

-Several pre-synaptic neurons synapse w/ a single post-synaptic neuron

61
Q

2 Types of Synapses

A
  1. Electrical Synapses

2. Chemical Synapses

62
Q

Enteric Nervous System

A

Enteric Nervous System (ENS)

  • Consists of neurons of enteric plexuses in gut wall
  • Independent of CNS + ANS
  • Communicates w/ CNS via ANS
  • Monitors stretch in gut wall + chemical composition of luminal environment
  • Stimulates GI smooth muscle contractions + stimulates exocrine gland secretions
  • Also involuntary
63
Q

3 Gated Channel Subtypes

A
  1. Voltage-gated
  2. Ligand-gated
  3. Mechanically-gated
64
Q

Reverberating Circuits

A

-Input recycles, allowing prolonged output

65
Q

Subcellular Locations of Ligand-gated Channels

A
  • Dendrites & somas of motor neurons & interneurons
  • Dendrites of unipolar & bipolar sensory neurons
  • Motor end plates of skeletal muscle cells
66
Q

Simple Series Circuits

A

-Two neurons connect to each other and one neuron connects to the first two

67
Q

6 Steps of Neurotransmitter Substances

A
  1. AP depolarizes end-bulb membrane
  2. Opening of voltage-gated Ca+2 channels
  3. Influx of Ca+2
  4. Exocytotic release of contents of synaptic vesicles (neurotransmitters)
  5. Neurotransmitter diffusion across gap
  6. Neurotransmitter binding to receptors of post-synaptic cell membrane
68
Q

Schwann Cells

A

Schwann Cells = “Neurolemmocytes”

  • Responsible for myelination of some PNS Fibers (Provides electrical insulation)
  • Myelin sheaths formed by many Schwann cells wrapping around each PNS fiber
  • Nodes of Ranvier = Gaps between Schwann Cells (Enable rapid nerve impulse conduction, AKA “Saltatory Conduction”)
69
Q

2 Nervous Tissue Types

A
  1. Neurons = Used to conduct nerve impulses

2. Neuroglial Cells = Used to support, protect, + nourish neurons

70
Q

Hypokinesis

A

Inadequate dopamine levels; caused by Parkinson’s DIsease

71
Q

Sensory Neurons

A

Sensory Neurons = Mostly uni-polar

  • 2 long axonic extensions; one segment from periphery w/ dendrites, one segment to CNS w/ terminal synaptic end-bulbs
  • Bipolar neurons found in retina, inner ear + olfactory epithelium
  • Conduct nerve impulses from peripheral body parts to CNS
  • AKA “Afferent Neurons”
72
Q

All-or-None Principle

A
  • If a stimulus is strong enough to reach the trigger zone threshold, an AP will propagate along the neuronal fiber at constant & maximum strength
  • If threshold isn’t reached, no AP occurs
  • If stimulus goes beyond threshold, AP will occur, but still at the same strength
73
Q

Nerves

A

A bundle of PNS fibers surrounded by connective tissue

74
Q

4 Types of CNS Neuroglia

A
  1. Astrocytes
  2. Microgilal Cells
  3. Ependymal Cells
  4. Oligodendrocytes
75
Q

2 Possible Outcomes of Neurotransmitter Substances

A
  1. Very small partial depolarization of post-synaptic membrane (excitatory post-synaptic potential; EPSP)
  2. Very small partial hyperpolarization of post-synaptic membrane (inhibitory post-synaptic potential; IPSP)
    * Information transfer only happens one way pre-synap. cell -> post-synap. cell
76
Q

Glycine

A
  • Inhibitory neurotransmitter in CNS
  • Used by 1/2 of synapses in spinal cord
  • Inhibitory glycinergic neurons (Renshaw cells) hyperpolarize lower motor neurons
77
Q

Voltage-gated Channels

A
  • Gates open when membrane depolarizes
  • Depolarization allows nerve & muscle cells to propagate action potentials along their membranes
  • Found in axonal membranes of neurons & in muscle sarcolemma & T-tubules
  • Subcellular locations: Motor neurons & interneurons, unipolar & bipolar sensory neurons, skeletal muscle cells
78
Q

Purines

A
  • ATP, ADP, AMP, adenosine, etc. are all examples of purines
  • All are excitatory
  • Mediates “purinergic neurotransmission”
  • In PNS, some neurons release ATP & noradrenaline or ATP & ACh
79
Q

Dopamine

A
  • A catecholamine (made from tyrosine by decaroboxylation and terminated by cellular uptake)
  • Responsible for pleasure, emotions addiction & schizophrenia
  • Modulates skeletal muscle activity of pyramidal pathway
80
Q

Synapse

A

Synapse = Functional junction between 2 neurons/ between a neuron & an effector / between 2 effector cells

81
Q

Neurotransmitter Substances

A

Transmission via chemicals at synapses (Causes synaptic delay, approx. 0.5 msecs)

82
Q

Serotonin

A
  • Made from tryptophan by decarboxylation
  • Released by neurons of raphe nuclei
  • Responsible for sensory perception, appetite, body temperature, mood & sleep
  • May be involved in anorexia, depression & sleep disorders
  • SSRIs prevent re-uptake
83
Q

3 Nerve Types

A
  1. Sensory = Contain only sensory fibers + carry nerve impulses from peripheral receptors to CNS
  2. Motor = Contain only motor fibers + carry impulses from CNS to peripheral effectors
  3. Mixed = Contain both sensory & motor fibers + carry impulses both to & from CNS
84
Q

5 Types of Neural Circuits

A
  1. Simple Series CIrcuits
  2. Diverging Circuits
  3. Converging Circuits
  4. Reverberating Circuits
  5. Parallel After-discharge Circuits
85
Q

Ligand-gated Channels

A
  • Open when hormones/neurotransmitters bind to receptors
  • Ionotropic receptors: Receptor & channel are the same protein
  • Metabotropic receptors: Receptor & channel are located on 2 different proteins
  • Other components: A G-protein & a 2nd messenger system
  • Subcellular locations: Same as voltage-gated channels
  • Opening of one ligand-gated channel = small graded potential
86
Q

Inhibitory Neurotransmitters

A
  • Hyperpolarize post-synaptic membrane; creates IPSP

- IPSP summation = electrical potential further away from threshold for firing

87
Q

4 Factors Affecting Speed of AP Conduction

A
  1. Myelination
  2. Fiber Diameter
  3. Temperature
  4. Anesthetics & Neurotoxins
88
Q

2 Ways to Interpret Stimulus Intensity

A
  1. AP Frequency = The more frequently an AP is fired, the stronger the stimulus is
  2. Size of Sensory Field = The bigger the affected area of the stimulus, the stronger the stimulus is
89
Q

Depolarization

A

Depolarization (+30 mV), caused by inflow of Na+ from opening of voltage-gated Na+ channels (Only occurs if threshold is reached)
*Approx. 20,000 Na+ ions flow inward

90
Q

Excitatory Neurotransmitters

A
  • Increase likelihood of AP
  • Depolarize post-synaptic membrane; creates EPSP
  • Summation of EPSP’s = Increased chance threshold for firing reached
91
Q

Different AP Durations

A

Nerves: 1-2 msec
Skeletal Muscle: 1-5 msec
-electrical events mechanical events

92
Q

Carbon Monoxide

A

CO functions as an excitatory CNS neurotransmitter

93
Q

Amino Acids (4 Main Examples)

A
  1. Glutamate
  2. Aspartate
  3. GABA
  4. Glycine
94
Q

Ependymal Cells

A

Ependymal Cells

  • Line brain ventricles + central canal of spinal cord
  • Aid CSF circulation + monitor its composition
  • Also involved in the “blood-brain barrier”
95
Q

Dendrite

A

Dendrite = Short, branched, unmyelinated processes, stimulated by other neurons, conduct electrical impulses to cell body via afferent transmission

96
Q

Noradrenaline

A
  • A catecholamine (made from tyrosine by decaroboxylation and terminated by cellular uptake)
  • Responsible for arousal, mood, & dreaming
  • Some neurons release adrenaline
  • Both released as hormones
97
Q

3 Types of Summation

A
  1. Spatial = Many pre-synap. neurons release neurotransmitter at the same time
  2. Temporal = Rapid neurotransmiter release at different times by one pre-synap. neuron
  3. Mixed = Combo of both
98
Q

Antagonist

A

-Agents which block the action of a hormone/neurotransmitter, showing affinity but little/no efficacy (e.g., atropine & its derivatives like ipratropium)

99
Q

Anesthetics & Neurotoxins

A
  • Some block Na+ channel openings in axons, therefore blocking AP propagation
  • Novocaine=Anesthetic
  • Tetrodotoxin=Neurotoxin
100
Q

Glutamate & Aspartate

A
  • Excitatory neurotrasnmitters in CNS
  • NMDA-type glutamate receptors linked to Ca+2 channels
  • In brain hypoxia, decreased glutamate re-uptake leads to cell death of post-synap. neurons (“excitotoxicity”)
101
Q

3 Types of Chemical Synapses

A
  1. Axodendritic = Axon->Dendrite
  2. Axosomatic = Axon->Cell Body
  3. Axoaxonic = Axon->Axon
102
Q

Electrogenic Mode of Na+/K+ Pump

A
  • For every 3 Na+ pumped out, 2 K+ are pumped in

- Mainly functions to eliminate Na+ that leaks into cell & replace K+ that leaks out of the cell

103
Q

Strychnine Poisoning

A

When strychnine blocks glycine receptors on lower motor neuron in spinal cord, leading to skeletal muscles fully contracting, then eventually, death by asphyxiation

104
Q

4 Factors Affecting RMP

A
  1. Distribution of Different Ion Species
  2. Differences in Plasma Membrane Permeability to Ions
  3. Intracellular Ion Movement
  4. Electrogenic Mode of Na+/K+ Pump
105
Q

Non-systematic Naming of Neurons

A 
Purkinje Cells of Cerebellum
-Discovered by a Czech anatomist Jan Purkyne 
Pyramidal Cells
-Controls skeletal muscle activity
*Dendrites + axons are processes
*Axons AKA "Neuronal Fibers"
106
Q

2 Major Nervous System Divisions

A
  1. The Central Nervous System (CNS)

2. Peripheral Nervous System (PNS)

107
Q

Hypothalamic Releasing & Release Inhibiting Hormones

A
  • GHRH & GHIH are examples of releasing & release inhibiting hormones
  • Function to regulate the anterior pituitary hormones
108
Q

Receptor Binding

A

Neurotransmitters bind receptors in neuronal dendrite & cell body membranes; causes ligand-gated channels to open, creating small graded potentials

109
Q

Net Effect of Neurotransmitters

A

Balance of EPSPs & IPSPs

110
Q

Somatic Nervous System

A

Somatic Nervous System (SNS)

  • Sensory neurons from skin, head, body wall + extremities to CNS
  • Motor neurons from CNS to skeletal muscles
111
Q

Chemical Synapses

A

-Regions where axon terminal’s synaptic end-bulb comes very close to a 2nd cell (called the “neuro-muscular/-glandular/-neural” junction)

112
Q

3 Structural Classifications of Neurons

A
  1. Multipolar Neurons = Several short dendrites + one long axon
  2. Bipolar Neurons = One dendrite + One axon
  3. Unipolar Neurons = One process w/ the cell body on the side
113
Q

Cell Body

A

Cell Body = Soma; Contains nucleus, organelles + inclusions

  • Lipofuscin = colored cytoplasmic pigment inclusions
  • Nissl bodies = RER
  • Neurofibrils = Intermediate Filaments
  • Microtubules = Used for transportation from cell body to axon terminus
114
Q

Axon

A

Axon = Long projection, filled w/ axoplasm + surrounded by axolemma, may be myelinated, joins cell body at axon hillock, conducts nerve impulses away from cell body (Initial segment = “trigger zone”)

115
Q

Diverging Circuits

A

-One pre-synaptic neuron influences several post-synaptic neurons

BIOL1191 (13 decks)

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