The synapse is the functional contact relationship between nerve cell endings . It is a concept that comes from a Greek word that means "Union" or "link" .
Before continuing, it is necessary to specify the meaning of axon, since it is an integral part of the synapse. It is an extensive and fine neuronal prolongation that begins in a region called exon eminence, or from a dendrite, which is a branch of a nerve cell. Its appearance is conical and presents certain protuberances known as Ranvier nodules. It is worth mentioning that his membrane It is called axonema and when they are outside the central nervous system, they are covered by a sheath called myelin. Among the functions performed by axomas is the transmission of nerve impulses, both sending and receiving, although the first case is the most common.
This process communicative between neurons start with a chemical-electric discharge on the membrane of the emitting cell (presynaptic ). When said nerve impulse reaches the end of the axon , the neuron secretes a substance that lodges in the synaptic space between this transmitting neuron and the receiving neuron (postsynaptic ). In turn, this neurotransmitter is responsible for exciting another neuron.
According to the type of transmission of the impulse nervous, the synapse can be classified as electric or chemistry . In the electric synapse , the pre and postsynaptic processes are continuous due to the cytoplasmic union by tubular protein molecules, which allow the stimulus to pass from one cell to another without the need for chemical mediation. In this way, the electrical synapse provides low resistance between neurons and a minimum delay in synaptic transmission since there is no chemical mediator.
The chemical synapse It is the most common type of synapse. In these cases, the neurotransmitter acts as bridge Between the two neurons, it diffuses through the synaptic space and adheres to the receptors, which are special molecules of proteins located in the postsynaptic membrane.
The Union of the postsynaptic membrane neurotransmitters and receptors generates changes in membrane permeability, while the nature of the neurotransmitter and the receptor molecule determines whether the effect produced is excitation or inhibition of the postsynaptic neuron. By the way, synaptic transmissions are presented in three predominant ways, which are:
* excitement, when it increases the chances of an action potential occurring;
* inhibition, if you reduce these possibilities;
* modulation, in the case where you modify the frequency or the pattern of the tasks carried out by the cells that participate in the transmission in question.
It should be mentioned that the exciter and inhibitor transmissions represent the most important forces of any neuronal circuit.
In a different area, the concept of social synapse refers to that tie invisible that is created among people, even among strangers, in situations such as a catastrophe. It is a very unique union of forces, in pursuit of a generally humanitarian objective; If this is not achieved successfully, then the suffering is collective and occurs at levels that remind us that we are all living beings, while if it is fulfilled, the satisfaction is greater than that experienced by a personal achievement.
As it is a union that does not require a Contact physical or a previous knowledge of the rest of the people who understand this emotional network, the social synapse speaks more of an approach to our roots as a species than of an interpersonal relationship. That is why even in the era of the Internet and mobile phones we are able to empathize with the victims of a tsunami in a country that we may never visit.