Exam 1 Flashcards
(113 cards)
1
Q
What are the divisions of the nervous system? (2)
A
- central nervous system
- peripheral nervous system
2
Q
Central Nervous System
A
neurons of CNS reside entirely within the brain and spinal cord
3
Q
Peripheral Nervous System (PNS) (2)
A
- neurons of the PNS allow the central nervous system to communicate with the periphery of the body
- contains spinal and cranial nerves
4
Q
Cranial Nerves
A
nerves that bypass the spinal cord
5
Q
What are some responsibilities of the cranial nerves? (3)
A
- sense of smell
- sight
- ability to move the eyes
6
Q
What are the divisions of the peripheral nervous system? (2)
A
- somatic
- autonomic
7
Q
Somatic Division (2)
A
- carries information between the CNS and the body parts
- allows brain to receive sensory information and control body movements
8
Q
Autonomic Division
A
allows the CNS to communicate with the organs of the body and occurs unconsciously
9
Q
What are the divisions within the autonomic nervous system? (2)
A
- sympathetic division
- parasympathetic division
10
Q
Sympathetic Division
A
fight or flight
11
Q
Parasympathetic
A
rest and restore
12
Q
What is the spinal cord protected by?
A
bony vertebrae
13
Q
What are the brain and spinal cord both protected by? (2)
A
meninges
14
Q
Meninges
A
three layers of protective tissue
15
Q
What are the names of the meninges? (3)
A
- pia
- arachnoid
- dura mater
16
Q
What is the process of a signal passing through the spinal cord?
A
carries tactile information from the skin up to the brain and from the brain to control body movements
17
Q
Central Portion of Spinal Cord (2)
A
- shaped like a butterfly
- contains cell bodies of neurons whose axons can cause muscles to contract
18
Q
Central Canal
A
runs through the length of the spinal cord and connects to the brain’s fluid filled ventricles
19
Q
Why is cerebrospinal fluid beneficial to the central canal and ventricles? (4)
A
- helps keep the brain buoyant
- acts as a cushion from mechanical damage
- assists in maintaining chemical stability
- carries nutrients to the brain
20
Q
Brainstem
A
connects the cerebrum to the spinal cord and cerebellum
21
Q
What are the sections of the brain stem? (3)
A
- midbrain
- pons
- medulla oblongata
22
Q
Medulla & Pons (3)
A
- contribute to process critical for maintaining life (respiration, cardiovascular control)
- sleep and arousal
- basic sensory and motor responses
23
Q
Midbrain (2)
A
- contains the cell bodies of dopamine neurons that play a key role in reinforcement learning
- contains superior colliculi and inferior colliculi
24
Q
Superior Colliculi
A
direct attention to visual stimuli
25
Inferior Colliculi
direct attention to auditory stimuli
26
Cerebellum (2)
- plays a key role in bodily balance, coordinating body movements
- involved in timing, temporal prediction, attention and learning
27
Thalamus (2)
- made of 30 nuclei, each of which transmits a specific kind of cognitive, sensory, or motor information to the cortex
- relay station for information
28
Hypothalamus (4)
important in...
- motivated behaviors
- stress
- maintaining body temperature
- sleep/wake cycle
29
Pituitary Gland
pea sixed gland that releases hormones important for growth, metabolism, and reproduction
30
Basal Ganglia
- collection of brain regions critical for voluntary behaviors
- motor memory
31
What are the two main components of the limbic system? (2)
- amygdala
- hippocampus
32
Amygdala
learns to recognize signs of imminent threat and of emotional significance
33
Hippocampus (2)
- critical for storing memories of our experiences
- episodic memory
34
Cerebral Cortex
carries out complex cognitive processes, such as language
35
What are the lobes of the cerebral cortex? (4)
- occipital
- temporal
- parietal
- frontal
36
What is the occipital lobe responsible for?
vision
37
What is the temporal lobe responsible for?
hearing
38
What is the parietal lobe responsible for?
tactile/sensation
39
What is the frontal lobe responsible for?
movement
40
What are some main fissures and sulci in the brain? (3)
- longitudinal fissure
- central sulcus
- lateral sulcus
41
Gray Matter
cell bodies and dendrites
42
White Matter
myelinated axons
43
Ventricles
hollow areas containing cerebrospinal fluid
44
Magnetic Resonance Imaging (MRI)
based on perturbation of water molecules in the brain with a radio frequency pulse within a magnetic field
45
fMRI
detects the blood oxygen level-dependent changes
46
EEG
records the electrical signals of the brain by using electrodes attached to your scalp
47
What are the planes of view of the brain? (3)
- axial view
- coronal view
- sagittal view
48
What are the cells of the nervous system? (2)
- neurons
- glia
49
What are the major components of a neuron? (4)
- dendrites
- cell body
- axon
- terminal
50
Dendrites
receive information
51
Cell Body (2)
- contains the organelles of the neuron
- collects information
52
Axon
transmits an electrical signal the to the terminal
53
Terminal
end of the neuron
54
Synaptic Cleft
space where neurons release neurotransmitters cross to communicate with receiving neurons
55
What is the process of neurotransmission? (4)
1) the neuron send an electrical signal down its axon
2) neurotransmitter is released from its terminals into the synaptic cleft
3) the neurotransmitter crosses synaptic cleft and binds to receptors on dendrites of a receiving neuron
4) receiving neuron sends signal down its axon
56
Neurotransmission
the communication between neurons
57
What are the types of neurons? (3)
- sensory neuron
- motor neuron
- pyramidal neuron
58
What are the types of glial cells? (5)
- Schwann cell
- oligodendrocyte
- microglial cell
- astrocyte
- radial
59
Glial Cells
contributes to neuronal function in important ways
60
Oligodendrocytes (2)
- insulation of the axons of the nerve cells in the CNS
- a single cells can be wrapped around several axons
61
Schwann Cells (2)
- produce myelin in the peripheral nerves that target body parts and organs
- involved in maintenance and regeneration of motor and sensory neurons of the PNS
62
Microglia (2)
- small cells that remove the debris left behind by neurons that are damaged or dead
- acts as the brain's own immune system, getting rid of toxins and pathogens
63
Astrocytes (3)
- star-shaped calls that store substances for future use by nearby neurons
- important in blood-brain barrier
- end-feet from astrocytes extend to surround blood vessels and provide support to the endothelial cells of the blood brain barrier
64
Radial glia
form a kind of structure of 'scaffolding' that helps guide newly born neurons to their final destinations in the brain
65
What are myelinated surfaces on the axon called?
internodes
66
What are unmyelinated surfaces on axons called?
nodes of Ranvier
67
Blood-brain Barrier (2)
- crucial immunological feature of the bloodstream that prevents any random chemicals circulating in blood from entering the brain
- formed primarily from tight junctions between endothelial cells
68
What are neurons activated by?
the entry of sodium ions
69
What is outside of the neuron?
high concentrations of sodium and chloride ions in the extracellular fluid
70
What is inside the neuron? (2)
- large negatively charged proteins
- potassium ions
71
What happens when sodium channels open?
sodium ions can move from the extracellular fluid to the inside of the neuron
72
What are two factors that cause sodium to pass through ion channels when they open? (2)
- diffusion
- electrostatic pressure
73
Electrostatic Pressure
positive charge attracts the negative charge
74
What is an example of neuron excitation? (3)
1) The sensory neuron responds to the heat of the cup
2) It sends a signal to a spinal cord neuron which passes the information to a motor neuron
3) The motor neuron activates muscles that cause the and to open and the cup to drop
75
What is an example of neuron inhibition? (4)
1) The sensory neuron responds to the heat of the cup
2) It send a signal that excites the spinal cord neuron
3) The brain recognizes that the cup is expensive and send a signal that inhibits the spinal cord neuron
4) The inhibitory signal from the brain cancels out the heat signal from the sensory neuron
76
What do sodium ions pass through?
ion channels
77
Ion Channels
passes through little gates within the wall of the neuron
78
What happens when enough sodium enters the neuron?
the neuron is depolarized and sends a signal along its axon
79
What happens when action potential reaches the axon terminals?
a neurotransmitter is released, crossing the synaptic cleft and exciting a receiving neuron
80
Membrane Potential
the charge inside compared to outside the neuron
81
What is the resting potential of a neuron?
-70 mV
82
Polarized
when the inside and outside of a neuron are very different in charge
83
Firing Threshold
a critical level of depolarization for the neuron to fire that the membrane potential must reach
84
Where is the firing threshold reached?
axon hillock
85
What are the steps in action potential? (4)
1) The cell is at its resting membrane potential of -70mV
2) Na+ gates open, causing Na+ to bring positive charge inside the cell (depolarization)
3) K+ gates open, causing K+ to carry positive charge outside the cell
4) Na+/K+ pump brings the neuron back to resting potential
86
Sodium-Potassium Pump (2)
- a protein embedded within the neuronal membrane
- for every 3 Na+ pumped out, 2 K+ are pumped in
87
Saltatory Conduction (2)
- when the action potential jumps from one node to the next
- greatly increases the speed of the action potential as it sweeps across the axon
88
What is the process of the release of neurotransmitters? (5)
1) Action potential arrives at the axon terminal
2) Calcium ion channels open causing calcium to rush in
3) The inflow of Ca+ causes neurotransmitter-filled vesicles to fuse with the membrane at the axon terminal
4) Exocytosis occurs and the neurotransmitters are released into the synaptic cleft
5) Neurotransmitters bind to a receptor on the postsynaptic neuron
89
Exocytosis
the merging of the vesicle with the membrane allowing for the secretion of its contents
90
How are neurotransmitter cleared from the synapse? (2)
- reuptake into presynaptic neuron
- degradation by enzymes into inactive components
91
What are the most abundant neurotransmitters in the brain? (2)
- glutamate
- GABA
92
Glutamate (2)
- excitatory
- depolarizes neurons to which it binds
93
GABA (2)
- inhibitory
- moves the membrane potential further from threshold and hyperpolarizes the neuron which it inhibits
94
What happens when a neurotransmitter binds to the receptor?
an ion channel at the core of the receptor opens
95
EPSP (2)
- excitatory postsynaptic potential
- a depolarization, which increases the neuron's likelihood of firing
96
IPSP (2)
- inhibitory postsynaptic potential
- hyperpolarization, and decreases the neurons' likelihood of firing
97
When can a neuron undergo hyperpolarization?
when an inhibitory neurotransmitter binds to receptors that cause the opening of chloride channels allowing Cl- ions to enter the neuron
98
Spatial Summation
inputs arriving simultaneously at different spatial locations of a neuron can add together
99
Temporal Summation
inputs arriving quickly in succession at the same time location can add together
100
What happens as EPSPs and IPSPs as they move along the membrane?
they diminish
101
Gap Junction
narrow gaps between presynaptic and postsynaptic neurons that allow direct flow of ions between neurons spread excitation more rapidly
102
Where do gap junctions exist?
cardiac muscle
103
Recurrent Neurons
involve loop signals back and forth allowing them to remain active over a period of time
104
Divergent
small number of neurons broadcast to a large # of recipients
105
Convergent
many neurons send signals to few neurons
106
Agonist
a drug that mimic or enhances activity of neurotransmitters
107
Antagonist
a drug that blocks or reduces the effects of neurotransmitters
108
L-DOPA
increases neurotransmitter synthesis in dopamine neurons
109
MDMA
increases neurotransmitter release in dopamine, norepinephrine, and serotonin neurons
110
Heroin
binds to opiate receptors, mimicking the effects of endogenous opiates
111
Zoloft & Prozac
block neurotransmitter reuptake in serotonin neurons, increasing serotonin concentration in the synapse
112
What drugs are examples of agonists? (4)
- L-DOPA
- MDMA
- Heroin
- SSRIs
113
What drugs are examples of antagonists? (2)
- Haldol
- Clozapine
