EPSP

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=== In the Central Nervous System (CNS)  ===
 
=== In the Central Nervous System (CNS)  ===
  
The Central Nervous System (CNS) is made up of the brain and the spinal chord, it receives information from the nervous system, where neurons are the building blocks of the CNS. (1) Many inputs from hundreds of other [[Neuron|neurons]] are received by a single neuron which then can form [[Synapse|synapses]] with many thousands of other [[Cell|cells]]. This type of neuronal transmission is known as [https://teaching.ncl.ac.uk/bms/wiki/index.php/Convergence convergence], where a small number of [https://teaching.ncl.ac.uk/bms/wiki/index.php/Presynaptic_and_postsynaptic_neurons presynaptic neurons] can affect a large number of postsynaptic neurons, forming branches called collateral axons. The following are examples of convergence where some will create an [https://teaching.ncl.ac.uk/bms/wiki/index.php/Action_potential action potential] and some won't. 
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The Central Nervous System (CNS) is made up of the brain and the spinal chord, it receives information from the nervous system, where neurons are the building blocks of the CNS. <ref>(1)</ref>Many inputs from hundreds of other [[Neuron|neurons]] are received by a single neuron which then can form [[Synapse|synapses]] with many thousands of other [[Cell|cells]]. This type of neuronal transmission is known as [https://teaching.ncl.ac.uk/bms/wiki/index.php/Convergence convergence], where a small number of [https://teaching.ncl.ac.uk/bms/wiki/index.php/Presynaptic_and_postsynaptic_neurons presynaptic neurons] can affect a large number of postsynaptic neurons, forming branches called collateral axons. The following are examples of convergence where some will create an [https://teaching.ncl.ac.uk/bms/wiki/index.php/Action_potential action potential] and some won't.&nbsp;  
  
'''Process:''' When there is an electrical impules and the [https://teaching.ncl.ac.uk/bms/wiki/index.php/Neurotransmitter neurotransmitter] binds the to the channel on the [https://en.wikipedia.org/wiki/Chemical_synapse postsynaptic membrane], the channel opens.If sodium channels open, then Na+ enter the cell→ [https://en.wikipedia.org/wiki/Excitatory_postsynaptic_potential EPSP] (positive), but if K+ or chloro channels open, then they will leave the cell→ [https://en.wikipedia.org/wiki/Inhibitory_postsynaptic_potential IPSP] (negative).<br>
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=== '''Type of Potentials&nbsp;''' ===
  
*Temporal Summation:&nbsp;
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Among these synapses on a single neuron, some get excited when others get inhibited. In the [https://en.wikipedia.org/wiki/Excitatory_synapse excitatory synapse], neurotransmitter is released which then causes a small [https://en.wikipedia.org/wiki/Depolarization depolarisation] within the postsynaptic membrane, naming: excitatory postsynaptic potential (EPSP).
*Spaital Summation:&nbsp;Neurons fire EPSP, which is positive due to sodium ions, each EPSP is subthreshold, meaning there is no action potential, but if subthreshold reaches the trigger zone at the same time, together, they will createa suprathreshold, which will create an action potential.
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*Postsynaptic Inhibition&nbsp;
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=== Type of Potentials  ===
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On the other hand, the neurotransmitter which is released from an [https://en.wikipedia.org/wiki/Inhibitory_postsynaptic_potential inhibitory synapse] causes a small [https://en.wikipedia.org/wiki/Hyperpolarization_(biology) hyperpolarization] called: an Inhibitory Postsynaptic Potential (IPSP).
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'''Process:''' When there is an electrical impules and the [https://teaching.ncl.ac.uk/bms/wiki/index.php/Neurotransmitter neurotransmitter] binds the to the channel on the [https://en.wikipedia.org/wiki/Chemical_synapse postsynaptic membrane], the channel opens.If sodium channels open, then Na+ enter the cell→ [https://en.wikipedia.org/wiki/Excitatory_postsynaptic_potential EPSP] (positive), but if K+ or chloro channels open, then they will leave the cell→ [https://en.wikipedia.org/wiki/Inhibitory_postsynaptic_potential IPSP] (negative).<br>
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*<u>Temporal Summation:</u>&nbsp;Occur from one presynaptic neuron. This is when the [https://en.wikipedia.org/wiki/Graded_potential graded potential] occur at a time that is so close to each other but from the same presynaptic neuron, therefore the summed potential hits [https://teaching.ncl.ac.uk/bms/wiki/index.php/Threshold_potential threshold potential] and triggers an action potential.&nbsp;<ref>(2)</ref>
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*<u>Spaital Summation:</u>&nbsp;Neurons fire EPSP, which is positive due to sodium ions, each EPSP is subthreshold, meaning there is no action potential, but if subthreshold reaches the [https://en.wikipedia.org/wiki/Trigger_zone trigger zone] at the same time, together, they will createa suprathreshold, which will create an action potential.
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*<u>Postsynaptic Inhibition:</u> There is no action potential because the graded potential do not reach threshold potential when they reach the trigger zone.&nbsp;<u></u><br>
  
Among these synapses on a single neuron, some get excited when others get inhibited. In the [[Excitatory synapse|excitatory synapse]], [[Neurotransmitter|neurotransmitter]] is released which then causes a small [[Depolarisation|depolarisation]] within the [[Postsynaptic membrane|postsynaptic membrane]], naming: excitatory postsynaptic potential (EPSP).
 
  
On the other hand, the neurotransmitter which is released from an [[Inhibitiory synapse|inhibitory synapse]] causes a small [[Hyperpolarization|hyperpolarization]] called: an [[Inhibitory postsynaptic potential|inhibitory postsynaptic potential]] (IPSP)<ref>Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K., and Watson, J.(2005), Molecular Biology of the Cell, 5th edn, Garland.</ref>.
 
  
 
=== Reference  ===
 
=== Reference  ===
  
1. Cherry K. Structure and Function of the Central Nervous System [Internet]. Verywell Mind. 2018 [cited 6 December 2018]. Available from: https://www.verywellmind.com/what-is-the-central-nervous-system-2794981
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1. Cherry K. Structure and Function of the Central Nervous System [Internet]. Verywell Mind. 2018 [cited 6 December 2018]. Available from: https://www.verywellmind.com/what-is-the-central-nervous-system-2794981  
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2. Dharani K. Molecular-Grid Model. The Biology of Thought [Internet]. 2015 [cited 6 December 2018];:123-142. Available from: https://www.sciencedirect.com/science/article/pii/B9780128009000000075

Revision as of 20:08, 6 December 2018

In the Central Nervous System (CNS)

The Central Nervous System (CNS) is made up of the brain and the spinal chord, it receives information from the nervous system, where neurons are the building blocks of the CNS. [1]Many inputs from hundreds of other neurons are received by a single neuron which then can form synapses with many thousands of other cells. This type of neuronal transmission is known as convergence, where a small number of presynaptic neurons can affect a large number of postsynaptic neurons, forming branches called collateral axons. The following are examples of convergence where some will create an action potential and some won't. 

Type of Potentials 

Among these synapses on a single neuron, some get excited when others get inhibited. In the excitatory synapse, neurotransmitter is released which then causes a small depolarisation within the postsynaptic membrane, naming: excitatory postsynaptic potential (EPSP).

On the other hand, the neurotransmitter which is released from an inhibitory synapse causes a small hyperpolarization called: an Inhibitory Postsynaptic Potential (IPSP).

Process: When there is an electrical impules and the neurotransmitter binds the to the channel on the postsynaptic membrane, the channel opens.If sodium channels open, then Na+ enter the cell→ EPSP (positive), but if K+ or chloro channels open, then they will leave the cell→ IPSP (negative).


Reference

1. Cherry K. Structure and Function of the Central Nervous System [Internet]. Verywell Mind. 2018 [cited 6 December 2018]. Available from: https://www.verywellmind.com/what-is-the-central-nervous-system-2794981

2. Dharani K. Molecular-Grid Model. The Biology of Thought [Internet]. 2015 [cited 6 December 2018];:123-142. Available from: https://www.sciencedirect.com/science/article/pii/B9780128009000000075


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