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The electrical impulse causes chemicals called neurotransmitters to be released from the axon terminals of the pre-synaptic neuron which diffuseacross the synaptic cleft and fit into receptors on the post-synaptic neuron.
In an excitatory synapse, the presence of the neurotransmitters in the receptors of ligand-gated ion pores cause those pores to open and allow sodium ions into the post-synaptic neuron, which results in an electrotonic signal being conducted down the dendrite and soma to the axon hillock, which may initiate an action potential in the axon if enough signals are summed up at the axon hillock to reach a trigger value.
When an impulse arrives at a synapse, neurotransmitters are released from the presynaptic neuron into the synaptic cleft. The neurotransmitters then bind to receptors on the postsynaptic neuron, leading to changes in the postsynaptic neuron's membrane potential. This can either excite or inhibit the postsynaptic neuron, influencing whether or not an action potential will be generated.
When a neural impulse reaches the end of a neuron, an axon terminal, it causes voltage-gated calcium ion pores to open, allowing calcium ions into the axon terminal, where a sequence of chemical actions causes vesicles (small bags) containing neurotransmitters to move into contact with the cell membrane, and fuse with it, releasing the neurotransmitters into the synaptic cleft (gap).
The neurotransmitters diffuse across the synaptic cleft, where they fit into receptor sites which are part of ligand-gated sodium ion pores, causing those pores to open, allowing sodium ions into the neuron. The sodium ions push one another down the dendrites and cell body (soma) to the axon hillock, in a process know as electrotonic conduction, which is a graded response since it can vary from weak to strong.
If a combination of many such signals, either from many dendrites or quickly from one or more, sums up to reach a trigger voltage, then an action potential will be triggered in the axon.
(Note that this is a description of what happens at an excitatory synapse; a similar but different process occurs at an inhibitory synapse. At an inhibitory synapse, the resulting membrane potential may serve to inhibit the action of other excitatory inputs.)
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What is the name of the region where two neurons are in done contact is known as?
synapse is that junction through which impulse can be transmitted from one neuron to another.
What happens when an impulse reaches the end of an axon?
It reaches the synapse and sends neurotransmitters to start a new impulse to the next neuron
What happens at the synapse between two neuron?
At the synapse, the electrical impulse between the two neutrons at synapse set of chain chemical reactions which create a chemical impulse at the synapse.
Where does an impulse move from on neuron to the other?
The impulse has to cross over a synapse to another neuron or an effector.
On which direction does an impulse go across a synapse?
An impulse travels in one direction across a synapse, from the presynaptic neuron to the postsynaptic neuron. This ensures that the signal transmission in the nervous system is unidirectional.
What is the name of the region where two neurons are in done contact is known as?
synapse is that junction through which impulse can be transmitted from one neuron to another.
What happens when an impulse reaches the end of an axon?
It reaches the synapse and sends neurotransmitters to start a new impulse to the next neuron
How does the impulse jump the synapse?
Chemical diffusion
A small space across which an impulse travels to move from one neuron to another?
It is most definitely a synapse.
What happens to the body when the receptors that remove catecholamines from a synapse have very low activity?
No impulse is transmitted. Hence the all or nothing principal.
What happens at the synapse between two neuron?
At the synapse, the electrical impulse between the two neutrons at synapse set of chain chemical reactions which create a chemical impulse at the synapse.
What carries an impulse across a synapse to a muscle?
neurons?
Where does an impulse move from on neuron to the other?
The impulse has to cross over a synapse to another neuron or an effector.
What structures cross the synapse to generate the next impulse?
Neurotransmitters.
The junction where one neuron can transfer an impulse to another is called what?
synapse
Is a nerve message also called a synapse?
No, a nerve message is not called a synapse. A synapse is the junction between two nerve cells where a nerve impulse is transmitted from one cell to another.
On which direction does an impulse go across a synapse?
An impulse travels in one direction across a synapse, from the presynaptic neuron to the postsynaptic neuron. This ensures that the signal transmission in the nervous system is unidirectional.
