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Is there any synaptic delay in communication from pre-synaptic neuron to post-synaptic neuron?
Yes, when speaking of a chemical synapse; but no, not so much, when speaking of an electrotonic (gap junction) synapse.
There are two types of synapses in the nervous system: chemical synapses, and electrical synapses (also know as electrotonic synapses or gap junctions).
Chemical synapses have a small gap between two neurons, called the synaptic cleft, about 30nm across. At this gap, the two neurons do not touch (except for small molecules projecting from each and sticking to one another so as to keep the neurons in place to maintain the synapse; they are called synaptic adhesion molecules); the two neurons do not exchange their interior cellular fluid, the cytosol, nor any ions or other solutes. On receipt of a neural impulse, the pre-synaptic neuron releases Neurotransmitter chemicals into the synaptic cleft, which then diffuse across the synaptic cleft to the post-synaptic neuron, where they fit into receptors there and cause ligand-gated ion pores to open in the post-synaptic neuron, allowing sodium ions into it, which is the beginning of the neural signal in that neuron. The release of the neurotransmitter, its diffusion across the gap, the opening of the ligand-gated ion pores, and the entry of sodium ions takes a comparative long time, with the result that the synaptic delay for a chemical synapse is approximately 2 ms.
Electrical synapses have a much smaller gap between neurons, about 3.5nm, with pore structures spanning the gap, which allows ions in the pre-synaptic neuron to pass directly into the post-synaptic neuron. Since there is no need for the pre-synaptic neuron to release neurotransmitters, nor for them to diffuse across a comparatively large gap, nor to cause ligand-gated pores to open, the synaptic delay for an electrical synapse is shorter, approximately 0.2ms.
However, the difference in synaptic delay between chemical and electrical synapses may be less for mammals than for cold-blooded animals.
What else can I help you with?
What is a presynaptic neuron?
a neuron from the axon terminal of which an electrical impulse is transmitted across a synaptic cleft to the cell body or one or more dendrites of a postsynaptic neuron by the release of a chemical neurotransmitter.
What is an example of a presynaptic cell?
An example of a presynaptic cell is a neuron that releases neurotransmitters into the synaptic cleft to communicate with the postsynaptic cell.
When two neurons are separated by a synapse which two parts of the neurons meet?
In a synapse, the terminal of the presynaptic neuron and the dendrite or cell body of the postsynaptic neuron meet. The presynaptic neuron releases neurotransmitters into the synaptic cleft, where they bind to receptors on the postsynaptic neuron, allowing for communication between the two neurons.
What are the synaptic events?
Synaptic events refer to the processes involved in communication between neurons at synapses. These events include neurotransmitter release from the presynaptic neuron, binding of neurotransmitters to receptors on the postsynaptic neuron, and subsequent changes in the postsynaptic neuron's membrane potential. This can lead to excitation or inhibition of the postsynaptic neuron based on the type of neurotransmitter and receptors involved.
Where at a synapse which direction does transmission usually occur?
At a synapse, transmission typically occurs from the presynaptic neuron to the postsynaptic neuron. The presynaptic neuron releases neurotransmitters into the synaptic cleft, which then bind to receptors on the postsynaptic neuron's membrane, facilitating the transmission of signals. This unidirectional flow is essential for proper neuronal communication and signal processing in the nervous system.
How does presynaptic nerve impulses get to postsynaptic nerve impulses?
Presynaptic nerve impulses trigger the release of neurotransmitters from synaptic vesicles at the axon terminal into the synaptic cleft. These neurotransmitters then bind to specific receptors on the postsynaptic membrane, leading to changes in the postsynaptic neuron's membrane potential. If the change is sufficient to reach the threshold, an action potential is generated in the postsynaptic neuron, allowing the signal to continue propagating. This process facilitates communication between neurons in the nervous system.
What is the name of the tiny gap the neurotransmitter has to diffuse across to reach the membrane of the postsynaptic neuron?
The tiny gap that the neurotransmitter has to diffuse across to reach the membrane of the postsynaptic neuron is called the synaptic cleft. It separates the axon terminal of the presynaptic neuron from the dendrite of the postsynaptic neuron.
How does neurotransmitters initiate depolarization?
Let's picture a presynaptic neuron, a synaptic cleft, and a postsynaptic neuron. An action potential reaches the terminal of a presynaptic neurone and triggers an opening of Ca ions enters into the depolarized terminal. This influx of Ca ions causes the presynaptic vesicles to fuse with the presynaptic membrane. This releases the neurotransmitters into the synaptic cleft. The neurotransmitters diffuse through the synaptic cleft and bind to specific postsynaptic membrane receptors. This binding changes the receptors into a ion channel that allows cations like Na to enter into the postsynaptic neuron. As Na enters the postsynaptic membrane, it begins to depolarize and an action potential is generated.
What is a presynaptic terminal?
A presynaptic terminal is the part of a neuron that releases neurotransmitters into the synaptic cleft during neurotransmission. Located at the end of an axon, it contains synaptic vesicles filled with these chemical messengers. When an action potential reaches the presynaptic terminal, it triggers the release of neurotransmitters, which then bind to receptors on the postsynaptic neuron, facilitating communication between neurons. This process is essential for the functioning of the nervous system.
What are the three parts of the synapse and what are their functions?
The three parts of a synapse are the presynaptic terminal, the synaptic cleft, and the postsynaptic membrane. The presynaptic terminal releases neurotransmitters into the synaptic cleft, which is the gap between the two neurons. These neurotransmitters then bind to receptors on the postsynaptic membrane, leading to changes in the postsynaptic neuron's activity. This process enables communication between neurons and is essential for transmitting signals throughout the nervous system.
How do neurotransmitters transmit signals across the synapse?
after impulse conductionby postsynaptic neurons is initiated, neurotransmitters activity is rapidly terminated. Either one or both of two mechanisms cause this. Some neurotransmitters molecules difuseout of the synaptic cleft back into synaptic knobs
When a presynaptic neuron is stimulated in a patients body by an electrical current neurotransmitters are released from the?
The synapse between pre synaptic and post synaptic neuron. Here the acetylcholine is released. It is destroyed by the enzyme acetylcholinesterase in milliseconds, once the impulse is passed to the post synaptic neuron
