The nerve impulse. Afector tissue. Neural circuits

To test the changes and transformations that occur in living organisms and how these are transmitted both inside and outside, sometimes deeply affecting our health and appearance, it is necessary to understand the elaboration electrochemical nerve impulse.

We turn to this consideration:

The nerve impulse
Applying a suitable stimulus to a neuron produces a local change in their conditions of rest which, if sufficiently severe, spreads throughout the cell. This process is perfectly tested in pilot studies and very clearly observed when working with the squid giant nerve fibers.

The plasma membrane of the neuron, like any living cell, this polarized, having an unequal distribution of the electric charges, which in turn contributes to cellular balance, be positive outside and negative inside.

This electrical imbalance-which in turn keeps the balance depends on the cell-membrane permeability different for different ions. The large intracellular organic anions can not diffuse negative polarity to the outside, while potassium (K), negative polarity, is spread with relative ease in both directions, but instead the permeability for sodium (Na), also positive, much smaller and, moreover, the protoplasm has the ability to actively expel the sodium ion, this mechanism which is called

*Automatic Translation