Chapter 3 Flashcards
1
Q
Tetanus
A
- block inhibitory responses by preventing the pre-sympathetic relapse of GABA
Symptoms: uncontrolled muscles spasms, lockjaw, progresses to breaking muscles, death
2
Q
Parkinson’s disease
A
- deficiency of dopamine in the basal nuclei
Symptoms: muscular rigidity, involuntary tremors
3
Q
What is the treatment for PD
A
Leva-Dopa
—> precursor of dopamine
4
Q
Effect of Cocaine on the synapse
A
- generates long-term modular adaptions
- cocaine leads to increased dopamine activity
- the number or dopamine receptors is reduced in response to glut, so the user must increase the dosage to satisfy the post synaptic cells
5
Q
Presynaptic facilation
A
- release of neurotransmitters in enhanced
6
Q
Presynaptic inhibition
A
- amount of neurotransmitters released is reduced
7
Q
Neuropeptides
A
- larger
- synthesized in the ER or golgi complex
- slow prolonged response
- lower concentrations
8
Q
Neurotransmitters
A
- small, rapid acting
- synthesized in the synaptic vesicles in the cytoplasm
- mainly amino acids
- typically trigger the opening of specific ion channels the bring about change in the post synaptic neuron’s (EPSP or IPSP)
9
Q
Inhibitory synapse
A
IPSP
- moves the synaptic neuron farther from threshold
- leakage of k; hyoerpolarization
- cl efflux
10
Q
Excitatory Synapse
A
EPSP
- both ions are increased at the same time
- neurons is easier to bring to threshold
- excite the next neuron
11
Q
MS
A
- demyelination’s disease
Symptoms: fatigue, wheelchair bound, loos of vision, muscle weakness
Cause: herpes 4 and 6, environmental
12
Q
Oligodendrocytes
A
- myelin forming cells in the CNS
- not not have regenerative ability
13
Q
Schwann cells
A
- form myelin in the PNS
- form regeneration tube
- provide neurotrophic factors
14
Q
Satellite cells
A
- form casual around the body
- in PNS
15
Q
Astrocytes
A
- secrete paracrine signals
- form tight junctions (BBB)
- provide neurotrophic nature
16
Q
Microglia
A
- brains immune cells
- scavengers
17
Q
Epidymal cells
A
- in CNS
- secrete cerebralspinal fluid
- act as stem cells
18
Q
Where are epidymal cells located
A
Hippocampus
19
Q
Modes of Ranvier
A
- where the axon is bare and exposed to the ECF
- can produce action potential ( has a high concentration of voltage gated na channels)
20
Q
Myelin
A
-80% lipids, 20% proteins
- insulator to prevent current leakage
21
Q
Variable of speed of conduction
A
- myelinated or unmyelinated
- diameter of the finer (larger = faster)
22
Q
Saltatory conduction
A
- myelinated neurons
- jumps
- faster communication
- energy efficient
- travels longer distances
23
Q
Contiguous conduction
A
- unmyelinated fibres
- action potential spreads whole length of the neuron
24
Q
Voltage gated channels
A
- open and close in response to membrane potential
25
Leak channels
- open all the time
- unregulated leakage of ions
26
Na - k concentration
2-3
27
Na
Extracellular: 150
Intracellular: 15
Relative permubility: 1
28
K
Extracellular: 5
Intracellular: 150
Relative permubility: 50-75
29
A
Extracellular: 0
Intracellular: 65
Relative permubiality: 0
30
Membrane potential
- difference charge between the ICF and ECF
- exhibited by all membranes
31
Depolarization
- increased permubility of na (na influx)
-“ climbing”
- upward
32
Repolarization
- increased k permubility
- falling
- downward movement
33
Hypolarization
Dip
- leakage of k into the cell
34
Relative refractory period
- na gates close; k gates open
- last part of repolarization and hyperpolarization
35
Absolute refractory period
- depolarization and repolarization
36
Action potential
- long distance signaling
- spends the entire length of the neuron
- rapid
- positive feedback
37
Mechanically gated channels
- stretching or other mechanical deformation
Ex. Touch
38
Chemically gated channels
- change conformation in response to the binding of specific chemical messengers in a membrane receptor
Ex. Neurotransmitters
39
Thermally gated channels
- local changes in temp
40
Types of gated channels
- voltage
- chemically
- mechanically, temperature
41
Gated channels
- prevent ion passage through channels
- change in three dimensional shape of the protein to open/close
42
Graded potential
- short distance signaling
- variable strength
