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Axon hillock- a pyramidal shaped region where all axons originate from

Initial segment- an area just beyond the axon hillock where all the stimulatory and inhibitory signals coming into the neuron are algebraically summed and it is decided whether or not an action potential should propagate or not.

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The above describes the structure of the axon where the action potential is created.

However, the actual nerve impulse (action potential) is generated in a series of steps based on how the ion channels trigger.

In this respect the first segment of the nerve impulse is the stimulus, which has to trigger positive ion influx beyond a given threshold.

After that stimulus exceeds the threshold, it triggers the opening of ion channels which pump sodium ions into the axon and potassium ions out, thus increasing the net positive charge on the inside of the neuron, depolarizing it and initiating the action potential (the nerve impulse).

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Is a nerve message also called a synapse?

Nerve messages are called an impulse. Synapses are the space between two axons.


Where does a nerve impulse start?

A nerve impulse typically starts at the dendrites of a neuron, where it receives signals from other neurons or sensory receptors. These signals are then transmitted down the axon of the neuron to the axon terminals, where they can communicate with other neurons or target cells.


Which of the following types of nerve fiber possesses the fastest speed of impulse propagation?

Myelinated A fibers have the fastest speed of impulse propagation among nerve fibers.


The duration of a nerve impulse is approximately?

The duration of a nerve impulse is very short, typically around 1-2 milliseconds. This rapid transmission allows for quick communication between neurons and helps to coordinate various body functions.


The events of a nerve impulse?

The electrical impulse in a nerve cell begins when ions move through the cells surface through ion channels.The nerve impulse.A nerve impulse is a wave of excitation that quickly travels within the surface of a neurone (nerve cell). This nerve impulse usually travels on certain parts of the nerve cell: on a dendrite or an axon. Within a neurone the first event depends on the type of 'nerve impulse'; there are two important types:1- nerve impulses generated at dendrites2- self propagating nerve impulses (action potentials) that travel along the axonNerve impulses generated at dendrites.Dendrites feed into the 'cell body' (soma) of a neurone. Nerve impulses that are generated in these dendrites travel toward the cell body.A sequence of events occur at the surface of a dendrite when the nerve impulse is sparked. The first event is transduction; this involves the transformation of one form of energy outside the dendrite into electrical energy within the dendrite.Nerve impulses that travel along axons.Nerve cells often have many dendrites but often only have a single axon. The essential difference between the two parts of the nerve cell is:- in dendrites electrical impulses travel TOWARDS the cell body of the neurone- in the axon the electrical impulses travel AWAY from the cell body of the neuroneThe nerve impulse that travels along an axon begins at the 'base of the axon', where the cell body and axon merge. This site is called the 'axon hillock' and is found to be the site where the first event in the formation of a nerve impulse actually occurs. Again, the first event is transduction at the axon hillock.Conclusion; the first event.For both of the cases above, and for virtually any other case, the nerve impulse begins with a process of transduction. The electrical nerve impulse begins once the first 'ions' leave or enter the nerve cell. Usually sodium ions enter, sometimes calcium ions are the firs to enter, sometimes potassium ions are the first to leave.

Related Questions

What is quicker a nerve impulse or a hormone?

nerve impulse


Which travels quicker through the body a nerve impulse or a hormons?

a nerve impulse


How does a nerve impulse follow all or nothing principle?

How does a nerve impulse follow the all-or-nothing principle???


What pathway does a nerve impulse follow after initiated into a receptor?

nerve my a$$ nerve


Is an action potential necessary for a nerve impulse to occur?

Yes, an action potential is needed for a nerve impulse to occur.


Is a action potential necessary for a nerve impulse to occur?

Yes, an action potential is needed for a nerve impulse to occur.


What is a nerve impule transmitted by axons?

It is called a nerve impulse.


The neurotransmitters of a neutron enable a nerve impulse to do what?

Neurotransmitters in a neuron allow a nerve impulse to be transmitted from one neuron to another by crossing the synapse and binding to receptors on the receiving neuron. This triggers an electrical or chemical signal to continue the nerve impulse along the neural pathway.


What nerve receive the impulse?

receptors.


What is the difference between synaptic and nerve impulse transmission?

Synaptic transmission is chemical, while nerve impulse or axonal transmission is electrical.


What happens to a muscle when an electrical impulse from a nerve stops?

When the electrical impulse from a nerve stops, the muscle relaxes and returns to its resting state. This is because the nerve impulse initiates the release of calcium ions in the muscle cells, leading to muscle contraction. When the nerve impulse stops, the calcium ions are reabsorbed, causing the muscle to relax.


What does the axial do?

Carry a nerve impulse to the next nerve OR to an effector cell.