Neurotransmitters, Neurons and Synaptic Transmission Flashcards
The cell body of the neuron contains
the nucleas and mitochondria
The dendrites of a neuron are
branches on each neuron that receive information to trigger an action
The axon hillock is where the
nerve impulse is triggered from
The axon
transmits info to other cells
The myelin sheath are
layers of fatty deposits that provide insulation and help speed up the rate of message transmission
The axon terminal is the
end of the axon, seperated from the other neurons by a tiny gap
Neurotransmitters are
chemical messengers that act between neurons that are triggered by a change in the electrical potential of neuron itself
Action potential is
the actual method by which the nerve impulses pass down the axon of the neuron to stimulate the release if neurotransmitters
Neurons have a resting potential of
-70mV
When a neuron receives a message, this chemical message can either
stimulate an exitatory post synaptic potential or hyper polarise the neuron
An exitatory post synaptic potential is
when the neuron’s charge us depolarised and reduced
Hyper-polarising the neuron
increases its charge and stimulates inhibitory post synaptic potential
For action potential to be triggered, more
exitatory messages than inhibitory messages must be received
Action potential is usually triggered at
-55mV
The neuron that is sending the message is the pre synaptic neuron while the one receiving it is the
post synaptic neuron
In synaptic transmission, the cell’s action potential starts as small electrical impulses generated at the axon hillock, but once the message
reaches the terminal button it turns into a chemical message
When the impulse reaches the axon terminal during synaptic transmission, the neuron
can pass its chemical message to further neurons across the synaptic gap/cleft.
What are receptors on the post synaptic neuron designed to do?
bind to a specific neurotransmitter and absorb it
What happens to neurotransmitters that have not been absorbed?
They will be destroyed by enzymes in the synaptic gap/cleft or they will be absorbed again by the presynaptic neuron in a process called reuptake
Reuptake is
the process by which unused neurotransmitter molecules are absorbed back into the presynaptic neuron and then be destroyed by enzymes
What is the function of the neurotransmitter acetylcholine?
stimulates muscle contractions and is involved in motor control and movement, also necessary for cognitive functions such as attention as well as emotions such as anger and sexuality
What is the function of the neurotransmitter noradrenaline?
it is associated with emotion, attention, energy and alertness, particularly in mood control as well as sleeping and dreaming as well as learning
What is the function of the neurotransmitter dopamine?
Similar to noradrenaline, related to emotion and cognitive functions as well as posture and control of movement, associated with reinforcement in learning and hormonal regulation e.g pleasure
What is the function of the neurotransmitter serotonin?
mostly used for mood control, in the limbic system in the brain, involved in feeling pain, sleep, regulating body temp and hunger
