Hodgkin-Huxley Model Essay

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Research Question: To what extent do Hodgkin-Huxley models successfully define action potential generation of an organism mathematically?
Background information:
Action Potential is a moving exchange of ions that runs along the length of the axon. (http://webspace.ship.edu/cgboer/actionpot.html) To know more about action potential, we first need to understand what a neuron is and where in the neuron action potential occurs. Below is an annotated diagram of what a neuron looks like.

A sensory neuron- http://www.memrise.com/user/bex1308/
Action potential occurs in the cell body region of the neuron. Biologically, action potentials occur when a stimulus causes the cell membrane of the cell body to decrease in potential difference (a difference …show more content…

This potential can be obtained by Goldman-Hodgkin-Katz model. It was used to calculate the membrane potential when more than one channels were present in the plasma membrane of the cell, and open at the same time. It majorly depends on the permeability of membranes in use. Permeability refers to the ease in which ions can pass through membranes to reach the opposite side. The ions can never reach their equilibrium potentials because three ions are contributing to the membrane potential. Since equilibrium cannot be reached, an electrochemical driving force is generated which acts on the ions. It is derived by finding the difference between the membrane potential obtained and the equilibrium potential expected. The sign of the value of this force decides the direction of movement of ions. Since we have cations (positive ions), a positive value shows movement of ions outside the cell membrane and a negative value shows movement of ions inside the cell membrane. If the value is equal to that of the equilibrium potential, the driving force acting on the ion is 0. This means there is no movement of ions in or out of the cell membrane and a resting potential is attained. At this point, there are more sodium ions outside the cell membrane and more potassium ions inside the