Week 6 Flashcards
1
Q
Two Parts of the Nervous System
A
- Central Nervous System (CNS)
- Peripheral Nervous System (PNS)
2
Q
Central Nervous System (CNS)
A
- Brain & Spinal Cord
- Dorsal Cavity
- Cannot regenerate
3
Q
Peripheral Nervous System (PNS)
A
- everything BUT brain & spinal cord
- contains ganglion
4
Q
Ganglion
A
groups of cell bodies
5
Q
Function of the Nervous System
A
Communication in the body
6
Q
3 Parts to Communication in the NS
A
- Recieve Signal
- Respond to Signal
- Integration
7
Q
Receiving a Signal
A
- through sensation AKA stimulus
8
Q
Three Parts of Sensation
A
- Chemical (smell/taste)
- Physical (touch)
- Mechanical (hearing/touch)
9
Q
Two types of Responses
A
- Involuntary
- Voluntary
10
Q
Autonomic NS
A
- Involuntary response
- not in control
ex. breathing & digestion
11
Q
Somatic NS
A
- voluntary response
- in control
ex. moving the skeletal muscles
12
Q
Perception
A
making sense of the signal going to your brain
13
Q
Integration
A
deciding how to react to stimuli
14
Q
White Matter
A
myelin axons
15
Q
Grey Matter
A
cell bodies
16
Q
Two types of Cell in Nervous Tissue
A
- Neurons
- Glial Cells
17
Q
Neruons
A
carry the signal
18
Q
Glial Cells
A
support the neurons
19
Q
Convergence
A
- a lot of connections between neurons
- multiple pathways to do one thing
20
Q
Parts of the Neuron
A
- Soma
- Dendrite
- Axon
- Nodes of Ranvier
- Axon Terminal
- Synapse
21
Q
Soma
A
cell body/grey matter
22
Q
Dendrite
A
receives signal from other neurons
23
Q
Axon
A
carries signal to the axon terminal
24
Q
Node of Ranvier
A
space between myelin on the axon
25
Axon Terminal
end of the axon
26
Synapse
space between neurons
27
Types of Neurons
1. Unipolar
2. Multipolar
28
Unipolar Neuron
- one process leaves the cell
29
Where are unipolar neurons found?
In the Peripheral Nervous System
30
Multipolar Neuron
lots of processes leave the cell
31
Where are multipolar neurons found?
Found in the Central Nervous System
32
Types of Glial Cells in CNS
1. Astrocyte
2. microglia
3. oligodendrocyte
4. ependymal cell
33
Astrocyte
- supports the neurons/holds them in place
- Maintain the blood brain barrier (BBB)
34
Blood Brain Barrier (BBB)
keeps stuff out of the brain
35
Microglia
defense
36
Oligodendrocyte
makes myelin in the CNS
37
Ependymal Cell
makes cerebral spinal fluid (CSF)
38
Cerebral Spinal Fluid
cushions brain/keeps it safe
39
Types of Glial Cells in PNS
1. Satellite Cells
2. Schwann Cells
40
Satellite Cells
Supports neurons
41
Schwann Cells
-makes myelin in the PNS
-helps with nerve regeneration
42
Myelin
speeds up the signal of a neuron
43
How do neurons communicate?
Carrying an electric charge (Action Potential)
44
Action Potential (AP)
- electric charges carried to communicate between neurons
- ALL or NOTHING
45
How does the brain differentiate between stimulus?
-frequency of AP is what defines signal in the brain
- different amounts of AP mean different things in the brain
46
Channel Protein
-helps cells cross the membrane
-not always open
- requires something to help open them up
ex. Sodium-Potassium Pump
47
Sodium-Potassium Pump (Na+/K+)
- pumps 3 sodium out of the cell and 2 potassium in the cell
48
Acetylcholine
neurotransmitter that makes muscles move
49
Types of Channel Proteins
1. Ligand-gated channel
2. Mechanically-gated channel
3. Voltage-gated channel
50
Ligand- Gated Channel
-lock and key
- channel opens with specific key
- found in the synapse
- NT is the key to open the channel
51
Mechanically-gated channel
uses sense of touch/pressure to open the channel
52
Voltage Gated Channel
- needs a specific voltage to open
- -55mV
53
Parts of the Action Potential
1. Threshold
2. Resting Potential
3. Depolarization
4. Repolarization
5. Hyperpolarization
54
How does an Action Potential Work?
1. Starts at Resting Potential (-70mV)
2. Stimulus is applied
- if it crosses -55mV, an AP is sent
- Sodium Channels OPEN
-Na rushing IN cell
- Cell gets POSITIVE (depolarization)
3. Na Channels CLOSE; K Channels OPEN (@ +30mV)
-K rushes OUT of cell
-cell become NEGATIVE (repolarization)
4. K Channels CLOSE slowly
- gets TOO NEGATIVE (hyperpolarization)
5. Na/K pump initiates
-brings cell back to RESTING
6. Arrives at resting potential (-70mV)
55
Continuous Conduction
-NO myelin on axon
- signal moves SLOW
56
Saltatory Conduction
- HAS myelin on axon
- signal jumps along the myelin & goes fast
57
How Connections are made in the Synapse
1. AP gets to axon terminal
2. Calcium channels OPEN
3. Calcium rushes IN cell
4. Calcium stimulate NT to be released INTO SYNAPSE
5. NT bind to ligand-gated receptor on the dendrite on next neuron
6. Ligand gate OPENS
-Na rushes IN cell
7. Action Potential occurs!!
