Synaptic Transmission Flashcards
What are the groups in which neurons communicate called?
Neural networks.
What are the gaps between neural networks called?
Synaptic gaps.
How are signals transmitted within a neuron?
Electrically, as an action potential.
What happens when the action potential reaches the end of the neuron?
It triggers the release of neurotransmitters.
What happens when the release of neurotransmitters is triggered?
The neurotransmitters travel across the gap to the next neuron.
What happens when neurotransmitters reach the next neuron?
The chemical message is recieved and converted back into an electrical signal.
What happens when an electrical impulse reaches the pre-synaptic terminal button?
It triggers vesicles to move to the pre-synaptic cell membrane.
What do synaptic vesicles do at the presynaptic membrane?
They fuse with the membrane and release neurotransmitters into the synaptic gap.
How do neurotransmitters travel across the synaptic gap?
They diffuse across the gap toward the post-synpatic neuron.
What happens if neurotransmitters fit the receptor sites on the post-synaptic neuron?
They are taken up, following the ‘lock and key’ model.
What happens once enough receptors have neurotransmitters bound to them?
The chemical message is converted back into an electrical impulse, continuing the signal along the next axon.
Why can only certain neurotransmitters unlock receptors on the post-synaptic neruon?
Because each neurotransmitter has its own specific molecular structure.
What analogy is used to describe how neurotrasnmitters fit into receptors?
The lock and key analogy.
What is the lock and key analogy?
Only the right neurotransmitter (key) fits the right receptor (lock).
What happens when a neurotransmitter binds to the correct receptor?
A specific ion channel in the membrane opens up.
What occurs when ion channels open in the post-synaptic neuron?
Ion flows into the neuron, creating a ‘potential’ in the dendrites.
What types of potentials can neurotransmitters cause in the post-synaptic neuron?
- Excitatory.
- Inhibitory.
What are excitatory neurotransmitters often referred to as?
‘On switches’.
What are excitatory neurotransmitters’ effect?
They make it more likely that the next neuron will fire.
What are inhibitory neurotransmitters often referred to as?
‘Off switches’.
What are inhibitory neurotransmitters’ effect?
Make it less likely that the next neuron will fire, effectively stopping the message.
What functions are inhibitory neurotransmitters responsible for?
- Calming the mind.
- Inducing sleep.
- Filtering out unneeded signals.
What happens when an excitatory neurotransmitter binds to receptors?
It triggers an excitatory post-synaptic potential.
What happens when an inhibitory neurotransmitter binds to receptors?
It results in an inhibitory post-synaptic potential.
