Action Potential Research Paper

If the frequency of action potentials in the excitatory presynaptic cell increases than the number of action potentials in the postsynaptic cell will increase as well. This is due to temporal summation of EPSP at very frequent times. This causes the postsynaptic cell to produce many action potential in succession.

3) Increasing frequency of stimulation of the trigger zone does not increases the production of the action potentials. This goes back to the threshold All or nothing theory.

A voltage-gated sodium ion channel opens when there is a change in the voltage of the membrane and allows sodium ions to flow across its electrochemical gradient. These voltage-gated channels are made up of amino acids and they aid in generating and moving an action potential down a membrane or axon (Brooker, Robert, 106).

If the nerve impulse is not released than it will not cause an action potential.

As well as these there are also the axon of the cell which is covered in myelin sheaths which carried information away from the cell body and hands the action potentials, these are small short bursts of change in the electrical charge of the axon membrane through openings of ion channels, off to the following neurons dendrites through terminal buttons at the end of the axons. Whenever an action potential is passed through these terminal buttons it releases a chemicals that pass on the action potential on to the next neuron through the terminal button and dendrite connection. The chemicals that are

Resting potentials require ions as they play a vital role in the process. In the surface membrane of a cell there are protein carriers. These actively pump Na+ ions out of the cytoplasm to the outside of the cell. At the

Once a presynaptic neuron is passive, an electrical current is spread along the length of the axon (Schiff, 2012). This is known as action potential (Pinel, 2011). Action potential happens once an abundant amount of depolarisation reaches the limit through the entry of sodium, by means of voltage gated sodium channels

When a membrane is excited depolarization begins. When the membrane depolarizes the resting membrane potential of -70 mV becomes less negative. When the membrane potential reaches 0 mV, indicating there is no charge difference across the membrane. the sodium ion channels start to close and potassium ion channels open. By the time the sodium ion channels finally close. The membrane potential has reached +35 mV. The opening of the potassium channels allows K+ to flow out of the cell down its electrochemical gradient ( ion of like charge are repelled from each other). The flow of K+ out of the cell causes the membrane potential to move in a negative direction. This is referred to as repolarization. ( Marieb & Mitchell, 2009). As the transmembrane potential comes back down towards its resting potential level and the potassium channels begins to close, the trasmembrane potential level goes just below -90mV, causing a brief period of hyperpolarization (Martini, Nath & Bartholomew, 2012). Finally, as the potassium channels close, the membrane turns back to its resting potential until it is excited or inhibited again.

The phrase “all-or-nothing” describes action potential because it only occurs when you reach threshold voltage.

Synaptic potential mentions to the distinction in voltage between within and outside of a postsynaptic neuron. It is the "approaching" flag of a neuron.

[3]. Boundless: Stages of the Action Potential [Internet]. Boundless Open Textbook: September 20, 2016. Available from:

Action potential is comprised of 5 distinct phases which are resting state, depolarization, rising phase, the falling phase and the undershoot. The resting phase happens when the cells are dormant, and all sodium and potassium channels are closed. Depolarization happens when a stimulus is applied and will cause the ligand gated sodium channel to undergo a conformation change which allows the ion channel to open and sodium can now pass through the sodium potential into the cell. The potassium channel is still closed. There must be a enough change in potential in order to allow depolarization to occur (also known as threshold potential).

To create a voltage across the cell membrane there must be Resting Potential: an electrical difference across the membrane of a nerve cell during an inactive period. This electrical difference generates a voltage that must be maintained to create a “ready state” that allows the cell to fire or create action potential across the axon. Without Resting Potential, there is no driving force for the main ions inside and outside of the cell.

Whenever the balance is altered, the process of transmitting electrical signals, which is called action potential initiates by carrying information across a neuron’s axon; which is called resting membrane potential. This process occurs as uneven ions distribution flow across cell membrane, creating electrical potential. As a result, the duration of active potential can be as fast as 1 ms. Similarly, the average resting membrane is between -40 mV and -80 mV. Since the membrane from inside is more negatively charged than the outside, it reflected on the negative average voltage readings of the resting membrane.

The electrical event that projects the signal along these distances is known as an action potential. The action potential runs from the axon hillock to the end of the axon where more synaptic contacts are made. Target cells of neurons include nerve cells in your brain, spinal cord, cells of your muscles and various glands.