Chapter 5 Flashcards
1
Q
Parts of the nervous system
A
Central nervous system
Peripheral nervous system
2
Q
Parts of peripheral nervous system
A
Motor
Sensory
3
Q
Parts of peripheral motor system
A
Autonomic nervous system
Skeletal
4
Q
Parts of sensory peripheral nervous system
A
Dorsal root ganglia
Cranial nerve ganglia
5
Q
Parts of the autonomic nervous system
A
Sympathetic
Parasympathetic
Enteric
6
Q
Draw out nervous system division map
A
7
Q
Central nervous system
A
Brain and spinal cord
8
Q
Peripheral nervous system
A
made of nerves, ganglia, sensory receptors and motor endings that are outside of brain and spinal cord
9
Q
Mechanoreceptors
A
Measure pressure, flex and flexion
10
Q
Chemoreceptors
A
Sensitive to chemicals in solution
11
Q
Nocioreceptors
A
Sense pain, respond to pinch and chemicals released from damaged tissues. Detect harm
12
Q
Afferent
A
Arriving at brain. Info collected by sensory system from in and out body moves toward the center and travels to brain
13
Q
Integration processing of information
A
Decision making.
Nervous system processes and interprets sensory info and makes decisions about what you do at each moment
14
Q
Efferent
A
Info leaving CNS. Goes back out through(somatic) motor division
15
Q
Four things that can happen after information processing
A
- Skeletal motor response
- Cardiac muscle
- Smooth muscle
- Glands
16
Q
Describe the travel of information through the nervous system
A
1.Information is sensed via receptors. Moves in afferent direction
- Information is processed by CNS during integration
- Info leaves in efferent direction and starts a motor response. One of 4 responses occurs
17
Q
Soma
A
Body
18
Q
Sympathetic
A
Fight or flight
19
Q
Parasympathetic
A
Rest and digest
Both at tug of war
20
Q
Autonomic tone
A
Dominance of sympathetic or parasympathetic nervous system
21
Q
Function Of nervous system
A
Collects sensory info from inside and outside of the body and coordinate appropriate response
22
Q
Thermo receptors
A
Respond to temperature changes
23
Q
Why Is there a tug of war between sympathetic and parasympathetic?
A
Muscles and glands innervated by both systems. Helps maintain homeostasis
24
Q
How many neurons in nervous system
A
100 billion
25
Enteric nervous system
Nervous system of GI tract. Supplies alimentary canal
26
Which nervous system can carry integration on its own separate from CNS
Enteric nervous system
Constantly communicates in microbiome of gut
27
Types of structures in peripheral nervous system
Spinal nerves
Ganglia
cranial nerves
Motor endings and receptors
28
Ganglia
Collection of cell bodies outside of CNS
29
Nuclei
Group of cell bodies inside of CNS
30
Why is the brain vascular?
The neurons are highly metabolically active
31
Neurons have a lot of which organelle
Mitochondria
32
What is the preferred energy source of neurons
Glucose
33
Gray matter is made of
Neuron cell bodies and unmyelinated axons
34
White matter is made of
Myelinated axons it is white because of cell membrane wrapping (myelin sheath)
35
Where does integration occur
Gray matter
36
What happens in Gray matter
Integration decision making and perception of senses
37
What happens in white matter?
Send signals to motor division
Highly efficient communication
38
Cortex
Outer layer of gray matter
39
Basal nuclei
Little bits of gray matter
Deep within white matter of cerebral hemispheres
Subcortical nuclei (under cortex)
Communicate with premotor cortex.
40
Nuclei
Clusters of neuron cell bodies in CNS
41
Basal nuclei function
Regulate movement
1.Starting and stopping
2.Repetitive motion (walking or riding bike)
3. Inhibit antagonistic movement (stops unwanted or unnecessary movement)
42
How are white matter and gray matter arranged in the spinal cord
White is on the outside gray is on the inside
opposite of brain
43
Sulcus
Crease and brain furrow less deep than fissure
44
Gyrus
Is a raised area of the brain
45
What is the function of sulci and gyri
Increase the amount of gray matter on surface area. More area for integration of information
46
Fissure
Deep longitudinal depression between two hemispheres. Deepest inward folds on brain
47
Foramen magnum
Large opening and occipital bone brain stem goes through
48
Medulla oblongata
Inferiormost part of the brain stem
49
Brainstem parts
Midbrain, pons, medulla oblongata
50
Midbrain
Relay sensory and motor information between the spinal cord and the rest of the brain.
51
Superior colliculi of the midbrain
Help control the movement of eyes head and neck in response to unexpected stimuli like loud noise or flash
52
What is the brain stem called after it enters the vertebrae
Spinal cord
53
Direction of tracts of white matter in the spinal cord
Afferent and efferent
54
Meninges
Protective layers of CNS
55
Describe the meninges from superficial to deep
Dura mater
arachnoid Mater
Pia Mater
56
Dura mater
Thick fibrous outermost toughest
Inward folds help secure the brain to the skull
Tough mother in Latin
Two layer fibrous connective tissue
57
Arachnoid Mater
Spider mother, weblike
Trabeculae
Above subarachnoid space
58
Pia Mater
Tender mother
Delicate connective tissue, has many tiny blood vessels. Things tightly to brain like plastic wrap
59
Describe the functions of the meninges
1.Protect and cover CNS
2. Protect blood vessels and enclose venous sinuses
3. Contains cerebrospinal fluid
4. Form partitions in the skull
60
Periosteal layer of Dura mater
Attaches to inner surface of skull. Not found in spinal cord
61
Meningeal layer of Dura mater
True external covering of brain
62
Subarachnoid space
Spider like extension secure the arachnoid Mater to the Pia Mater.
Houses cerebrospinal fluid and largest blood vessels serving the brain
63
Nerves
Pns fibers of somatic and autonomic neurons
64
Arachnoid granulations
Protrude superiorly through the dura mater and into the superior sagittal sinus
Absorb CSF into venous blood of the sinus
65
Meningitis
Inflammation of meninges.
Serious threat to brain it may spread to the CNS
66
Encephalitis
Brain inflammation
67
How is meningitis diagnosed
Obtaining sample of CSF via lumbar tap
68
Cerebrospinal fluid
Forms liquid cushion
Prevents brain from crushing under its own weight
Nourishment, similar to blood plasma
69
Brain functions
1. Perception and processing sensory stimuli
Execute voluntary motor responses and involuntary motor responses
3. Regulates homeostatic mechanisms
70
Spinal cord functions
1.Starts reflexes
2. Pathway from sensory and motor functions
71
Which parts of the spinal cord start reflexes
1. From ventral horn & lateral horn
72
Ventral horn
Somatic
73
Lateral horn
Autonomic (gray matter)
74
Ganglia is found in
PNS
75
Ganglia
Collection of nerve cell bodies outside of CNS
76
Function of ganglia
Receive sensory information by dorsal root and cranial ganglia
-tells viscera to move via the autonomic nervous system
77
Where do you process visual information
Occipital lobe
78
What are functional MRIs used for
Study the central nervous system and get diagnostic info
79
Function of myelination
Speeds up communication
80
What is the speed of an unmyelinated signal
3 to 30 m per second
81
What is the speed of a myelinated signal
300 M per second
82
Oligodendrocyte
Creates the myelin sheath in the central nervous system
Has cell body off to the side
83
Neuroglia
Nerve glue.
Support and maintain neurons
Outnumber the neurons
84
Schwann cells
Myelinate axons in the peripheral nervous system
85
Nodes of Ranvier
Bit of exposed axon exposed to extracellular environment
86
Explain saltatory conduction
The action potential travels between gaps of myelination.
Moves more rapidly. Only nodes of Ranvier have to be depolarized
87
Dendrites
Branching listeners.
Neuron process that receives electrical signals and takes it to soma
88
Synapse
Space where dendrite and axon interact .
Where pre and post synaptic neurons almost touch
89
Presynaptic neuron
Sends impulse to synapse
Sends
90
Postsynaptic neuron
Takes electrical signal away from synapse
Receives
91
Explain how action potentials travel down neurons
1. Impulse travels down axon to synaptic cleft
2. Releases NT at the end
3. Neurotransmitter binds to receptors of dendrites on postsynaptic neuron
92
Why are action potentials irreversible
The impulse travels in One direction
93
Describe the cell body of a neuron
Has normal cell components, lots of mitochondria, multiple nucleoli, endoplasmic reticulum has polyrbosomes
94
Polyribosome
Multiple ribosome. mRNA complex makes multiple copies of the same protein
95
Other names for polyrbosomes
Chromatophillic substance
Or Nissl bodies
96
Axon hillock
Where neuron narrows down to axon
97
What supports the axon from inside?
Neurofibrills
98
Where are neurotransmitters made?
Cell body. They travel to the synaptic knob
99
What goes down the axon?
Neurotransmitter,
Mitochondria,
Cell waste,
100
What happens to the things that are not needed at the end of the axon?
Goes back up
101
Electrical signal of an axon only moves in - direction(s)
One
102
Where does the electrical signal of a neuron start?
Axon hillock
Travels toward axon terminal into synaptic knobs
103
Unipolar neuron
One process comes from body
104
Bipolar neuron
Two processes extend from cell body
105
Multi-polar neuron
Multiple processes extend from cell body
1 axon many dendrites
106
Function of motor proteins
Move substances up and down the axon
107
Anterograde movement
Movement away from cell body
108
Retrograde movement
Move towards the cell body
109
Sensory neurons
Unipolar neurons
110
What happens in unipolar neurons during early development?
Axon and dendrites fuse
111
Dorsal root ganglia
Filled with bodies of unipolar sensory neurons in spinal cord
Collect sensory information from body and takes to the spinal cord and brain
112
Where can you find bipolar neurons?
Retina of the eye
113
90% of neurons in the central nervous system are
Multi-polar neurons one axon many dendrites
114
Which neurons can lack an axon?
Some vision neurons have no axon
115
What does the purkinje cell layer do?
Maps movements of the body and it's found in the cerebral cortex
In cerebellum
116
Proprioception
Body's ability to sense movement action and location
117
Tracts
Bundles of axons in the central nervous system.
Carries information (afferent) to brain
118
Nerve
Bundle of axons in the peripheral nervous system
119
Pyramidal cells found in
cerebral cortex
120
Cerebrum
Big part of brain
121
Cerebrum parts
Cerebral hemispheres
Cerebral cortex
White matter
Basal nuclei
122
Cerebellum
Proprioception
Most involved in producing smooth coordinates skeletal muscle activities
123
Where are olfactory receptors located?
Superior nasal cavity covered by mucous membranes
124
Olfactory neurons
Help smell things
125
Sensory neurons
Unipolar neurons that move electric impulses to the central nervous system
126
How many processes come out of a sensory neuron?
One
127
Relay neuron
Interneuron
Connect sensory neurons with motor neurons
128
What is the function of interneurons?
Move signal through the CNS pathways
129
Reflex
Automatic reaction to stimuli most simple neural pathway in the body
130
Only monosynaptic reflexes in the body
Stretch Reflexes
131
Monosynaptic reflex
involve a single synapse
132
Schwann cells
Individual cells from peripheral nervous system that make the myelin sheath
133
Why are they called oligodendrocytes?
They can myelinate multiple places on one axon or multiple axons
134
Myelin sheaths are made of
Lipids and proteins
135
What kind of information do Myelinsheaths conduct?
Sensory and motor information
136
Multiple sclerosis
Autoimmune
Immune system attacks myelin sheath
Erratic signals and poor signal strength
137
Guillain-Barre syndrome
Myelin sheath attacked in peripheral nervous system
138
Certain characteristics of myelin sheath in ____ let's axons regrow
Peripheral nervous system
139
Large bundles of neurons including the axons and myelination
Nerve
140
Astrocytes
Shaped like star most abundant CNS neuroglia
Controls exchanges between blood capillaries and neurons
Directs connection in new synapses
141
Blood-brain barrier importance
Prevent certain substances from going into brain blood capillaries
142
Describe astrocytes
Apportion of their extensions connect to capillaries.
Filters substances out of capillary
143
How do astrocytes control the chemical environment?
Collect leaked potassium ions
Recapture and recycle neurotransmitters
144
True or false medications can cross the blood-brain barrier
True
145
Microglial cells in CNS
Macrophages
Live in brain
Phagocytize pathogens cellular debris and metabolic waste products
146
Epyndymal cells
Found in ventricles of brain.
Line cavities of brain and spinal cord.
Produce CSF.
Have cilia that helps circulate CSF
147
Parts of a neuron
Axon
Dendrites
Soma
Synaptic knobs
148
Why is it important to get rid of debris?
Debris can power bacteria
149
Ventricles
Space pockets in brain filled with cerebral spinal fluid and lined with epyndymal cells
150
Functions of cerebrospinal fluid
Move wastes, cushion and protect
151
What are the glial cells of the peripheral nervous system
Schwan cells and satellite cells
152
Satellite cells
Support cells body in the peripheral nervous system
153
What does myelination look like in extra fast communication?
Wraps around multiple times
154
Neurofibrils
In the middle of axon
Intermediate filaments that maintain shape
155
Neurolemma
Outer layer of schwann cell lets the PNS neuron repair and regrow
156
How are Schwann cells used for repair?
1. Macrophages clean site of damage
2. Neurolemma forms tunnel
3. Neuron Targets reconnection of peripheral motor neuron with skeletal muscle.
Establishes reconnection between basement membrane and connective tissue below
157
What happens if a temperature is colder than the temperature you usually sense?
Will sense pain same if too hot
158
At rest the inside of a neuron is
Negative
159
Frey syndrome
Peripheral motor neurons reconnect incorrectly to the new target connect to sweat glands causes sweating instead of breaking down food through saliva
160
Which nervous system innervates the parotid gland?
parasympathetic
161
Explain how the nervous system works
1. Sensory receptors in skin are activated
2. Action potential (electrical charges)goes through the sensory axon
3.The inside of the axon goes from negative to positive (depolarization)
4. The action potential goes through the dorsal root ganglion
Goes into spinal cord. Action potential travels through tract.
5. Sensory axon enters spinal cord and synapses with the brain.
Interneuron between sensory neuron to area in gray matter
6. Second neuron projects into thalamus
7. Sensory pathway reaches the cerebral cortex. Decides what to do integration.
8. Upper motor neuron execute's motor command. Moves in efferent direction
9. Connects with lower motor neuron. Makes contact with lower motor neuron in spinal cord.
10. Lower motor neuron causes contraction of target skeletal muscle
162
Which cations are important for depolarization
Sodium and potassium
163
Ligand
Binds to receptor. chemical messenger
164
Which sensory information travels through the thalamus?
All except smell
165
What is the function of the thalamus?
Routes information to appropriate location
166
Neuromuscular junction
Innervated skeletal muscle
167
How do you make the inside of a cell positive?
Let sodium in
168
How do you make the inside of a cell negative?
Let potassium out through concentration. Gradient to reset
169
Extra and intracellular conditions for conduction of action potentials
External environment needs high concentration of sodium
Internal environment needs higher concentration of potassium than the outside
170
What is the neurotransmitter of skeletal muscles?
Acetylcholine
171
When does sodium start to enter the axon?
When the voltage is greater than the threshold value of negative 55 millivolts
172
When does the axon start to repolarize
When the voltage reaches positive 30 millivolts potassium starts to leave and sodium channels close
173
Is acetylcholine excitatory or inhibitory?
Can be both
174
Explain the function of ligandgated channels
1.When acetylcholine binds, the channel protein opens and things move down the concentration gradient.
2.Sodium rushes into cell calcium rushes into cell potassium leaves cell
175
Explain how mechanically gated channels work
1. Channel protein is always hollow.
When appropriate signal is received. Channel opens
Open in response to a physical deformation of receptor. Such as touch and pressure
176
Give an example of a mechanically gated channel
Thermoreceptor
177
Voltage-gated channels
Sense changes in voltage cell interior. Goes from negative to less negative.
Channels open and let certain ions go down. Concentration gradients
178
Types of voltage-gated channels in neurons
Voltage gated sodium channels. Potassium channels
179
Which ion concentration is higher in extracellular fluid?
Sodium
180
Which ions concentration is higher in intracellular fluid?
Potassium
181
Leaky channel
Sodium lets down concentration gradient in predictable regular interval. Autonomic nervous system adjusts to control base level heart rste
182
Charge on inside of axon is more
Negative
183
Give an example of leaky channels
Sodium channels in cardiac conduction system
184
EPSP
Excitatory post synaptic potential
Tell cell to do something
sends excitatory signal
185
IPSP
Inhibitory postsynaptic potentials
Tells neuron don't send signal
186
Where do signals add up
Axon hillock
187
How do EPSPs affect the charge
Make cell more positive
188
When do voltage-gated potassium channels open up?
After + 30 millivolts
189
What is hyperpolarization?
Potassium ions continue to leave cell
-becomes more negative than normal resting point
190
Normal resting point voltage of cells
-70 mV
191
What is the function of hyperpolarization
Keep signals from overlapping or going backward
192
Which channels are slower to close
Potassium channels
193
When do potassium channels open?
Positive 30 millivolts
194
How does the cell recover from hyperpolarization?
The sodium potassium pump restores concentration gradients
195
Approximate value of hyperpolarization
-92 mV
196
Explain how the sodium potassium pump moves
Three sodium out 2 potassium in
197
Why does the sodium potassium pump need energy?
Cause it moves against the concentration gradient.
Sodium goes back out where the concentration is higher. Potassium goes in to where it's more concentrated
198
Explain voltage changes in neurons
1. At rest -70mV
2. Stimulus applied
3. Depolarization ( voltage rises)
4. +30 and repolarization (voltage falls)
5. Hyperpolarization, and of AP
6. Return to rest
199
What causes hyperpolarization of the cell?
Potassium channels that are slow to close
200
Why do decisions of action potentials happen at the axon hillock
Because all dendrites collect different charges and they taper at the axon hillock
201
Calcium has higher concentration in
Extracellular fluid
202
Exocytosis
Vesicles merge with plasma membrane to release content into extracellular space
203
What happens when the action potential reaches the synaptic knob?
1. AP causes synaptic knob to make voltage gated calcium channels to open
2. Calcium goes in.
3. When calcium goes in and reaches a certain concentration. it tells vesicles with neurotransmitter to get released via exocytosis.
3. Neurotransmitter is released into the synaptic cleft
4. Neurotransmitter diffuses and binds to ligandgated channels. Often sodium channels. Sodium goes into next cell
204
Group C. Fibers
Nerve impulses move slowly because axons are nonmyelinated and small
No. Saltatory conduction
205
Group a fibers
Somatic sensory and motor fibers
Serve skin skeletal muscles and joints
Largest diameter thick myelin
206
Group B. Fibers
Lightly myelinated
Intermediate diameter
Transport impulses at average rate
207
Which system do B &C fibers serve?
Autonomic nervous system motor fibers serving visceral organs.
Visceral sensory fibers, smaller somatic sensory fibers, transmit sensory impulses from skin
208
What determines resting membrane potential
Distribution of sodium potassium, chlorine and plasma proteins
209
What can make the inside of a cell less negative
Influx of sodium or increase in extracellular potassium which reduces the amount of potassium leaving through leakage channels p
210
An influx of chlorine or a decrease in intracellular sodium can cause
Hyperpolarization
211
Absolute refractory period
Cannot respond to other stimulus sodium channels open and become an active as they open and then start to close
212
Relative refractory period
Cell can be stimulated with a stronger than normal stimulus
Sodium channels and resting state. Some potassium channels open resting potential reestablished
213
Leakage channels contribute to
Resting membrane potential
214
Describe the all or none phenomenon of action potentials
Action potential either occurs completely or does not happen if the threshold is not met
215
How is stimulus intensity coded?
Impulses per second.
Stronger stimuli generate action potentials more frequently than weaker stimuli.
Frequency not amplitude
216
Which substances are moved in anterograde movement
Mitochondria
Cytoskeletal elements
Membrane components used to renew axon plasma membrane
Enzymes needed to make neurotransmitters
217
Which substances are moved in retrograde movement?
Organelles returning to cell body to be recycled
Tell cell body about conditions at axon terminals delivers vesicles containing signal molecules
218
Which are the listeners of a neuron?
Cell body and dendrites
219
Which type of axonal transport allows certain viruses to circumvent the barrier created by astrocytes
Some viruses and bacterial toxins that damage neural tissues use retrograde axonal transport to reach cell body
220
Example of multipolar neurons
Motor neurons
221
Function of motor neurons
Carry impulses away from CNS to effector organs
222
A neuron with a distal peripheral process and a central process that extends to the central nervous system is most likely a
Sensory neuron
223
What does the distal peripheral process of a sensory neuron do?
Sensory receptor
224
What does the central process of a sensory neuron do?
Enter the central nervous system
225
Chiefly found in ganglia of PNS
Unipolar neurons
226
Most
Inter Neurons are confined within
CNS
227
What makes up 99% of neurons in the body?
Interneurons
228
Processes of interneurons
Multipolar
229
Process classification of sensory neurons
Unipolar
230
Parts of neurons
Dendrite soma axon and synapse
231
Collaterals
Multiple branches of axon's target different structures
232
Collaterals emerge from
Myelinated nerve at myelin sheath gaps
233
Where do you find short distance signals called grated potentials that travel toward the cell body?
Dendrites
234
Graded potential
Localized changes in membrane potential. Usually in dendrites or soma
235
What is the secretary region of a neuron?
Axon terminal
236
Norepinephrine
Neurotransmitter used by post ganglionic neurons in sympathetic nervous system
237
Function of norepinephrine
Feels good
Enhanced by amphetamines
Removal from synapse blocked by tricyclic, antidepressants and cocaine
238
Function of serotonin
Inhibitory
Indirect action via second messengers
Sleep appetite, nausea, migraine, headaches regulating mood
239
Which neurotransmitter acts as a natural opiate and inhibits pain?
Endorphins reduce pain perception under stress
240
Drugs that block this neurotransmitter relieve anxiety and depression
Serotonin
241
Spatial summation
Multiple local potentials occur at different places on the same cell at the same time. Post synaptic neuron is stimulated
by many pre-synaptic neurons
Huge numbers of receptors by neurotransmitters and start EPSPs
242
Feel good. Neurotransmitter deficient in Parkinson's disease
Dopamine
243
Involved in wakefulness appetite, control, learning and memory
Histamine
244
Grated potentials made at dendrites move through
Chemically gated ion channels
245
Differences between electrical and chemical synapses
Chemical: lake that two neuron shout across
Electrical: like doorway electrical synapses makes simple way of synchronizing brain activity
246
What kind of synapses are most abundant in the embryonic stage
Electrical synapses
247
Which circuit type is involved with precise mathematical calculations?
Parallel
248
Adenosine
Caffeine simultaneously blocking brain adenosine receptors.
Generally, inhibitory indirect action via second messengers
249
Serial processing
Whole system works in predictable All or nothing manner
250
Peptides with inhibitory opiate like actions
Endorphins
251
Neurons
Nervous system cell that generates and transmits electrical signals
252
Axon
Neuron process that carries action potentials away from body.
253
Impulse
Self propagating wave of depolarization
254
Neurotransmitters
Chemical messengers that help neurons communicate
255
Sensory receptors
Cell or part of cell specialized to respond to a stimulus
256
Somatic nervous system
Responsible for controlling voluntary movements and processing sensory information
257
Autonomic nervous system
Controls involuntary actions of the body
258
Synaptic cleft
Fluid filled space at a synapse
259
Sensory neurons
Sends sensory information from internal and external environment to CNS
260
Relationship between nuclei and interneurons
nuclei contain interneurons. modulate flow of information. interneurons within nuclei can have inhibitory or excitatory effects on the neurons they connect with.
261
Resting potential
-70 mV
262
Depolarization
Loss of state of polarity.
Loss of negative membrane potential
263
Repolarization
Return of the membrane potential to initial polarized state
264
Hyperpolarization
Membrane becomes more negative than resting membrane potential
265
Threshold potential
-55mV weakest stimulus capable of producing a response in an excitable tissue
266
Action potential
Brief electrical impulse that sends information
267
Acetylcholinesterase
Degrades acetylcholine and terminates it's action at the neuromuscular junction and synapses
268
Neuromuscular junction
Synaptic connection between terminal end of a motor nerve and a muscle
269
Convergence
Lets neuron receive input from many neurons in a network
270
Divergence
One neuron can communicate with many other neurons in a network
271
Neuronal pools
groups of interconnected neurons in CNS that work together to carry out a specific function.
272
Explain the roles of K, Na, Cl and Ca in developing an action potential
1. Potassium (K+): Potassium ions have a high concentration inside the cell compared to outside. This concentration gradient is maintained by the sodium-potassium pump. Potassium channels in the cell membrane allow K+ ions to flow out of the cell, making the interior of the cell more negative.
2. Sodium (Na+): Sodium ions have a higher concentration outside the cell compared to inside. Sodium channels in the cell membrane allow Na+ ions to flow into the cell, making the interior more positive. This influx of positive charge depolarizes the cell.
3. Chloride (Cl-): Chloride ions are also involved in establishing the resting membrane potential. Chloride channels allow Cl- ions to move across the cell membrane, helping to maintain the overall charge balance.
4. Calcium (Ca2+): While calcium is not as directly involved in establishing the resting membrane potential as K+, Na+, and Cl-, it plays a crucial role in cell signaling and neurotransmitter release. Changes in intracellular Ca2+ levels can modulate the membrane potential and affect cellular communication.
273
Difference between neurons and neuroglia
Neurons are the primary functional units of the nervous system, responsible for transmitting electrical and chemical signals. Neuroglia, or glial cells, provide support and protection for neurons, as well as maintaining homeostasis in the nervous system.
