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Synapses - A level Biology help puleez
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These are structures right ? I mean, a synapse is a pre synaptic knob a synaptic cleft and a post synaptic cell right ?
How can a synapse be excitatory and another be inhibitory ? Are the neurotransmitters in these synapses different ?
How can a synapse be excitatory and another be inhibitory ? Are the neurotransmitters in these synapses different ?
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#2
yes, synapses are the region that connects one neurone to another, or with a receptor/effector.
An excitatory synapse is a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell.
An inhibitory postsynaptic potential is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.
the neurotransmitters would likely be different.
An excitatory synapse is a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell.
An inhibitory postsynaptic potential is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.
the neurotransmitters would likely be different.
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#3
Synapses are either exitatory or inhibitory - it's more about how the neurotransmitters interact with the differnet structures.
Exitatory synapse - is basically just the normal passage of a neurotransmitters across the synapse (calcium caused vesicles to fuse etc etc)
Inhibitory synapse - this means an action potential is less likely to fire - remember all these synapses are different so it depends if the whole synapse structure in inhibitory - so if the synapse is inhibitory the neurotransmitter released causes chloride ion channels to open so chloride enters by facilitated diffusion. As well as the neurotransmitter causing the chloride channel to open it also causes a potassium channel to open so POSITIVE potassium ions leave the neurone into the synapse. So basically chloride (negatively charged) is entering and potassium (positively charged) is leaving and this combined effect makes the inside more negative and outside more positive which is known as HYPERPOLARISATION (where the synapse is extremely negative it's normally -65 mV but it goes down to -80 mV when the synapse is this negative an action potential cannot occur because it's further away from the threshold therefore making it inhibitory.
Sorry that was kind long winded but i hope that clarified something for you.
Exitatory synapse - is basically just the normal passage of a neurotransmitters across the synapse (calcium caused vesicles to fuse etc etc)
Inhibitory synapse - this means an action potential is less likely to fire - remember all these synapses are different so it depends if the whole synapse structure in inhibitory - so if the synapse is inhibitory the neurotransmitter released causes chloride ion channels to open so chloride enters by facilitated diffusion. As well as the neurotransmitter causing the chloride channel to open it also causes a potassium channel to open so POSITIVE potassium ions leave the neurone into the synapse. So basically chloride (negatively charged) is entering and potassium (positively charged) is leaving and this combined effect makes the inside more negative and outside more positive which is known as HYPERPOLARISATION (where the synapse is extremely negative it's normally -65 mV but it goes down to -80 mV when the synapse is this negative an action potential cannot occur because it's further away from the threshold therefore making it inhibitory.
Sorry that was kind long winded but i hope that clarified something for you.
(Original post by JacobBob)
These are structures right ? I mean, a synapse is a pre synaptic knob a synaptic cleft and a post synaptic cell right ?
How can a synapse be excitatory and another be inhibitory ? Are the neurotransmitters in these synapses different ?
These are structures right ? I mean, a synapse is a pre synaptic knob a synaptic cleft and a post synaptic cell right ?
How can a synapse be excitatory and another be inhibitory ? Are the neurotransmitters in these synapses different ?
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reply
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