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The action potential reaches the pre synaptic area, which opens a voltage sensitive Calcium ion gate, allowing calcium ions to move in via diffusion along an electrochemical gradient. The period of refraction (repolarisation) closes this gate.
The increased conc. of Calcium ions pushes vesicles with neurotransmitter to the presynaptic membrane, where they fuse and exocytosis causes the neurotransmitter to be released across the synaptic cleft. The NT binds to a receptor which opens Na+ channels on the postsynaptic membrane, allowing depolarisation due to Na+ diffusion which continues the action potential across the other neurone.
The neurotransmitters are broken down by enzymes or are reabsorbed by endocytosis into the presynaptic cleft, using energy from ATP.
Wiki User
∙ 15y ago
Wiki User
∙ 13y agoNerve impulses, which are electrical, do not jump across the synaptic gap at synapses. Instead, the arrival of a nerve impulse at the axon terminal triggers the release of chemicals called neurotransmitters from the axon terminal into the synaptic gap. The neurotransmitter molecules diffuse across the gap to the membrane of the postsynaptic cell, in effect serving as chemical messengers. There are molecules called receptors that stick off the membrane of the postsynaptic cells. In order to have any effect on the postsynaptic cell, a neurotransmitter molecule must fit onto a receptor. There are specific receptors for specific neurotransmitters, and the neurotransmitter molecule must fit onto the receptor precisely, as a key fits into a lock. When a neurotransmitter successfully fits ont a receptor, it causes changes in the postsynaptic cell, making it more (or less) likely to fire off a nerve impulse of its own.
Wiki User
∙ 12y agoIon channels open and action potentials and/or graded potentials are then able to begin.
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What is an electrical synapse?
Chemical synapses are much slower to react to stimuli. However chemical synapses transmit a signal with constant strength or even a signal that get stronger. This is called "gain." Electrical synapses are faster but have no "gain," the signal gets weaker as it travels along the synapse to other neurons. Electrical synapses are only used for applications where a reflex must be extremely fast. They are simple and allow for synchronized action. A benefit of electrical synapses is they will transmit signals in both directions. Chemical synapses have many important advantages as well. They are more complex and vary their signal strengths. Their functions are influenced by chemical outputs in the nervous system. Chemical synapses are the most common type.
It is said that synaptic connections form so quickly in the babys brain that by the time the baby is three it will have twice as many synapses as it will need later on How are these extra synapses?
they are eliminated when they are not used
How the brain connects things together?
With the Nervous System.
Part of the nerve cell that first receives the nervous impulse is the?
The dendrite of a neuron usually receives a chemical signal from another neuron, although a cell body (soma), or sometimes even an axon, of another neuron can receive the signal.Synapses which occur between an axon and a dendrite are called axodendritic synapses, while synapses between an axon and a cell body are called axosomatic synapses, and synapses between an axon and an axon are called axoaxonic synapses.
What is a statement regarding synapses?
Synapses are the connections between nerve cells. They transmit information from one nerve cell to the next. However, all nerve cells receive and make many synapses, so what the nerve cell actually does with the incoming signals can be quite complicated.
Where does synapses take place?
The synapses take place in the spinal cord
When does a human brain work best?
At birth, the synapses in the brain are most active at this time in a persons life.
What does the word synaptic mean?
The word synaptic is an adjective which means, pertaining to the synapses. So, I could describe dopamine as a chemical that has a synaptic function, as a neurotransmitter.
How does acpu and memory work together?
There is a very simple biological answer. The acpu and the memory synapses make sweet love then they are combined and work together.
How many synapses does the brain have?
The brain is estimated to have around 100 trillion synapses. These synapses are the connections between neurons that allow them to communicate with each other.
Are there synapses in peripheral nervous system?
There are synapses between each and every neuron in the entire nervous system; so yes, there are synapses in the peripheral section of the nervous system.
How would you describe a time when you had a difficulty and how you handled it?
I experienced a difficulty when a project deadline was moved up unexpectedly. I communicated with my team to prioritize tasks, adjusted schedules, and worked extra hours to meet the new deadline successfully.
Describe how transmission of impulses across synapses can be controlled?
They can be controlled by neurotransmitter levels, function, and by pre- and postsynaptic receptors, as well as by their component messengers and intermediaries (such as cyclic AMP and others).
What are the reaction that having a great time leaping across synapses?
There are no reactions, the end of a nerve produces a gas that goes across the synapses and creates the electrical impulse on the other side of the synapses and continues the message!
What has the author U Sandbank written?
U. Sandbank has written: 'The development of synapses' -- subject(s): Nervous system, Synapses
Which system involves a synapse?
All nerves have synapses, which are where the nerve junctions are located, so the nervous system involves synapses.
The venom of the black widow spider causes violent muscle contractions by flooding synapses with?
It floods the synapses with Acetycholine or ACh.
