NT + neurons Flashcards
NT + neurons
neuron structure + transmition of signals/ NT
A Neurone is between 1 mm to 1 m in length
💥🫛☘️
💥 this is the cell body which contains nucleus and little dendrites which are the tentacle-like bits that receive signals and convert them from chemical to eletrical signals for it be passed along the neutron
🫛 this is the axon which is made out of Little Myleene sheets which contain Schwann’s cells and These Sheaths are joined together by nodes of ranviers
The action potential is how nerve impulses passed down the axon to shatter the vesicles and release neurotransmitters
☘️ this is the axon terminal where there are little branch-like structures called axon terminals and at the end of these there are terminal buttons in these buttons neurotransmitters are stored in vesicles
Until released (exocytosis)
( this is where the electrical signal is converted into the chemical signal aka the neurotransmitters)
The neurotransmitter then passes through the synaptic gap into a specific receptor (lock and key)
What’s neurotransmitter bonds or receptor the ion channel opens and electrical signal probate itself along the length of the target cell then the neurotransmitter can be recycled by that target cell for it’s own use this takes place in the dendrites of the target cell
These neurotransmitters may be excitatory
this speeds up the firing rate of the action potential (Pulse)
The neurotransmitter could also be an inhibitory neurotransmitter
This slows down the firing rate (pulse) of the action potential
NT + neurons
types of neuron
There are three main types of neuron
motor = this type of neuron controls movements breathing and speaking by sending commands from the brain to the muscles to do an action
relay = this neuron allows for sensory and motor neurons to communicate
sensory = these are nerve cells that activate from sensory input from the environment
E.G. touch
NT + neurons
The Action Potential process
On the outside of neuron there is positive sodium ions and on the inside of a neuron there are negative potassium ions
Resting charge of a neuron is -70 mV
When event happens the ion channels open a little so the positive sodium ions enter the neuron
If the overall charge of the neuron gets to minus 55mv then depolarization occurs and the on channel fully opens and lots of sodium swarms in
If the overall charge of the neuron gets to 40mv then an electrical signal(action potential bracket passes down the axon which results in more ion channels opening as it goes past as this is an event
This action potential signal continues down to the axon terminal where it shatters the vesicles releasing neurotransmitters
After this there is hyperpolarization and the overall charge of the neuron drops below -70mV
This is due to a significant amount of sodium leaving the neuron to going back outside
some go back and stay inside of neuron and when that happens the overall charge of neuron stabilizers and the channel closes back at its resting potential of -70mv
NT + neurons
Serotonin
Serotonin is a neurotransmitter that is inhibitory
This means that slows down the rate in which the action potential fires
This neurone transmitter is the stabilizing mood
Low levels of serotonin means there’ll be more depression and anxiety
NT + neurons
Dopamine
Dopamine is excitatory neurotransmitter
Dopamine causes a euphoric experience
It also speeds up the rate in which action potential fires
NT + neurons
glutamate
Glutamate regulate dopamine serotonin so if there is more dope mean than seroton levels will decrease
as dopamine increases serotonin decreases
NT + neurons
Agonist (mimic NT effect so +/- rate of action potential firing)
Mimics the effects of a neurotransmitter
This causes the firing rate of the action potential to increase
NT + neurons
Antagonist (stops effect of NT by blocking receptors)
Reduces or stops the effect of a neural transmitter by binding to a receptor to block them
NT + neurons
Reuptake inhibitor (NT not reuptaken so builds up)
This block 3 uptake of the new and transmitter so more neurotransmitters stay in the signaps increasing its action
for example
Lots of serotonin builds up and then mood is super stableised
Methamphetamine
This increases dopamine and adrenaline and decreases serotonin
It also acts as a realtake inhibitor as it blocks the reuptake of dopamine which therefore allows it to build up and therefore create an even larger euphoric high
Short term:
Euphoric high increased
happiness and pleasure and
adrenaline increases the heart rate and breathing rate
this may last between 2 to 24 hours
Long term:
Due to low levels of serotonin this could lead a depression which could lead to more intake of method in the euphoric high this leads to an addiction
Heart issues including cardiac arrest
Mood fluctuations leading to poor mental health which may to schizophrenia
Heroin
Heron blocks the pain receptors which means there is no feelings of pain or feelings of sadness it also reduces the inhibitory effect of GABA on dopamine which means that there is more dopamine
Short Term:
chilled out
stopping pain receptors
euphoric experience
Long term: when the Heroine stops then you get withdrawal symptoms such as Insomnia diarrhea and pain
Overtime heroin desensitizers which means that these need more heroin to have to feel the same effects which then leads to body having the physical dependence on it also addiction
Evidence for drugs effecting NT
Diana Marinez et al 2012
gave rats heroin and showed that the dopam receptive had changed shape by using a PET scan from before and after giving the rat’s heroin this is objective and scientific evidence on how drugs can cause addiction and affect neurotransmitters
bad research for drugs effect NT (adiction)
Diana Marinez et al 2012
Evidences support this is not generalizable as in rats brains are similar to humans but not the same also drugs such as heroin may have different effects on humans and therefore the results cannot be generalized to a human population
evidence against Drugs effect NT (adiction)
The research of Alexander 1980 states that drugs do not cause addiction as he built a rat park for his rats
He addicted the rats to morphine and then gave them the option between tap water and water with Morphine in it almost all of the rats chose the normal water
This shows that drugs were not addictive and did not have that effect on neurotransmitters
