Nervous System Flashcards
(65 cards)
1
Q
Central Nervous System (CNS)
A
- Brain and spinal cord
- Command center
- Concious and subconsious
Integration
2
Q
Peripheral Nervous System (PNS)
A
- all nerves NOT in brain/spinal cord
- connects everything
- 31 spinal nerves
- 12 cranial nerves
3
Q
Sensory division (afferent)
A
- Sends impulses from the senses to the CNS
sensory input
4
Q
Motor division (efferent)
A
- sends impulses from the CNS to muscles & glands
response
5
Q
Sympathetic division
A
- Used in emergency situations (flight/fight/freeze)
6
Q
Parasympathetic division
A
- Reduces sympathetic responses
- Resting fxns digestion and urination
7
Q
Autonomic nervous System (ANS)
A
- Involuntary muscle control
8
Q
Somatic nervous System (SNS)
A
- Voluntary muscle control
- Reflexes skeletal motion
9
Q
Dendrites
A
- bring impulses towards the cell body
10
Q
Axon
A
- Sends impulses away from the cell body
- End in axon terminal
- Which release neurotransmitters to pass the impulse to the next neuron
11
Q
Myelin sheath
A
- Axons are wrapped in myelin (waxy insulation)
- Myelin is formed by Schwann cells wrapping around the axon
- Helps impulses move faster
12
Q
Nodes of ranvier
A
- gaps between myelin
13
Q
Cell body (soma)
A
- houses the organelles and recieves the impulse from dendrites
14
Q
Unipolar neurons
A
- 1 process of cell body
15
Q
Bipolar neurons
A
- 2 processes of cell body
16
Q
Multipolar neurons
A
- many processes
most common
17
Q
Where do afferent neurons carry impulses towards?
A
CNS
18
Q
Where do efferent neurons carry impulses away from?
A
CNS
19
Q
What connects efferent and afferent neurons?
A
Interneurons
20
Q
What do neuroglial cells do?
A
- the glue, support, and protection for neurons to do their jobs
21
Q
Astrocyte
A
- support and anchor neurons to surrounding capillaries
- facilitate exchange
22
Q
Microglia
A
- provides immune response to neurons in CNS
23
Q
What do phagocytes do?
A
- eat dead cells and invaders
24
Q
Ependymal cells
A
- secrete and circulate cerebral spinal fluid (CSF)
25
Oligodendrocytes
- provide the myelin insulation for neurons in the CNS
26
Satellite cells
- support and anchor neurons in the PNS
27
Schwann cells
- provide myelin insulation to neurons in the PNS
28
Which neuroglia cells are found in the CNS?
Astrocyte, microglia, ependymal, oligodendrocytes
29
Which neuroglia cells are found in the PNS?
Satellite cells, Schwann cells
30
As the impulse arrives...
sodium (on outside) rushes into the neuron and change the charge of the neuron
*action potential*
31
At rest...
inside of neuron=negatively charged enviorment outside=positively charged
*resting potential*
32
When the impulse reaches the synapse (end of nerve)
stimulates neurotransmitters and are released from the axon terminals. Causes channel to open to the next neuron continuing the impulse
33
Synaptic cleft
space between synapses
34
action potential
reverse of charge
35
Step 1 to an impulse
Impulse arrives and threshold is met
36
Step 2 to an impulse
Voltage gated Na+ channels are opened and Na+ enters the cells
37
Step 3 to an impulse
Voltage gated K+ channels are opened and K+ levels the cell, Na+ channels begin to rest
38
Step 4 to an impulse
Voltage gated K+ channels are still open, Na+ channels are in resting state
39
Step 5 to an impulse
Na+ K+ pump restores voltage to resting state
40
All or nothing response
A nerve impulse is an all or nothing response. Either the threshold is met and the impulse continued, or it is never started
41
Resting is...
polarized
42
Action potential is....
depolarization and repolarization
43
Step 1 to a synaptic transmission
Action potential (impulse) arrives at the pre synaptic terminal
44
Step 2 to a synaptic transmission
Ca+ channels open on pre synaptic terminal
45
Step 3 to a synaptic transmission
Synaptic vessles release neurotransmitters
46
Step 4 to a synaptic transmission
Neurotransmitters released into synapse bind to receptors on the next dendrite
47
Step 5 to a synaptic transmission
Na+ channels open on the dendrite to relay impulse
48
What are the 2 things that happen to left over neurotransmitters?
- reuptake protein
- enzymes can break them down
49
What are the order of the meninges layers? (surface to deep)
Dura mater, subdural space, arachnoid, sub arachnoid space, pia mater
50
Where is CSF found?
- between the arachnoid layer and the pia mater
51
What does CSF do?
- protects the brain by preventing it from contacting the skull
- maintains the blood brain barrier, which controls homeostasis for the brain and prevents infection
52
Where does CSF produce?
In the 4 ventricles: 2 lateral, 3rd and 4th (lateral and 3rd ventricles connected by interventricular foramen
53
Where is CSF secreated?
- in choroid plexuses of ventricles, then circulated before being reabsorbed by arachnoid granulations
54
Dura mater
- thick, tough layer with a subdural space
55
Arachnoid membrane
- thin, cobweb - like layer
subarachnoid space
56
Pia mater
- thin layer containing lots of blood vessles
57
Where does the spinal cord extend from?
From the medulla oblongata to the lumbar vertebrae
58
Where does it relay impulses between?
| cranial nerves
PNS and brain
59
Cross section
"butterfly" of grey matter surrounded by white matter
60
Afferent nerves
dorsal horns -> ventral horns -> efferent nerves
*sometimes interneurons between A and E
61
What does the reflex arc involve?
1.) receptor
2.) sensory neurons
3.) integration
4.) motor neurons
5.) effector
62
Reflexes are...
pre programmed responses
63
Endoneurium
surrounds each neuron
64
Perineurium
surrounds a group of neurons (fascicle)
65
Epineurium
surrounds a whole nerve
