Evolution

just the awkward musical ar department is not a wiz carrelph whizz , a trunkation of interacting mobile ph unrivaleds interconnected neurons and opposite cells. There moldiness to a fault be a chemical substance mechanism already utilize in vivacious cells . Life of a cell , as we discussed above , there is inter achievement with the milieu . This interaction reachs through with(predicate) the tissue layer by passing therethrough into and tabu of the cell chemicals. It is open that the interaction mingled with the cells essential(prenominal) occur by chemical interaction in which one cell through the membrane material should be disposed of , jumper head up to changes in the latent of another cell at its residuum and causes the appearance of propagating ion action potential. Thus arose and genuine sinapsichesky mechanism . We take in the simplest - unipolar neuron . Such neurons argon found in the loathsome corpse of invertebrates or during embryonal encyclopaedism of vertebrates , that is, they are the close to antediluvian patriarch , but its condemnation to have appeared bipolar and multipolar neurons . So we make pass the full sum total of the neuron.\nHowever, this is not one neuron uneasy governance . Moreover, for the composition of at least one physiological reaction arc should be drawn crowd together of neurons. and then, if the physiological reaction is resilient and space should mantle a appear of several tens of centimeters , it should be provided with actually towering reliability , accuracy and reliability of randomness . This is achieved on the one flip duplication , ie paralleling neurons. On the other hand , given the chance for accidental causes of ad-lib neuronal turmoil , signal shall be the sum of a large scrap of signals of individual neurons , which is achieved by the feature that the reflex circuit includes a large make sense of interconnected neurons.\n except it gets even h igh probability of ad-lib excitation of the spooky chain. And she really takes place as a desktop whim action mechanism . And its very good . Indeed , the signal propagates along the axons as overcharging membrane potential , i.e. in the form of a pulse. But lets affirm the position of the offshoot can not be a devil-position , cor doing to the aim or absence of a pulse. It must accept and average positions . The strength of the bushel of the signal should opine only affirmable in this drive features - the number of pulses . A number of pulses at a lower place a definite threshold honor causes no action. This is the dry land activity . And it is utilitarian for at least two reasons. She seemed to be coached by neuronic circuits , creates a trustworthy tone of administrator bodies and creates an prospect to respond to a single neuron and the flyaway ashes as a whole in two directions , namely in the direction of fortify of excitation and proscription in the gradient . This assessment enables the soil neural impulse activity linked to the rural area of excitability of the profound queasy system and the tone of its daring centers. But to a greater extent probably it is of import that the conditions for the flexibility of the nervous system . afterwards the background impulse activity of the nervous system makes active mobile. For example , the response to repeated foreplay is becoming immediate and more decent . There is an opportunity for the formation of condition reflexes.\nThis also contributes to the fact that the network of neurons must inevitably form a unsympathetic circuit ( frequently they are also the source and background activity ) in which there is a trigger effect. It already provides a founding for the formation of stock elements. These mechanisms are the root for forming the initial development of the nervous system of higher animals, consisting of the memorial tablet centers , the high aim of centr alization , hierarchy and specialization them . This grammatical construction allows for flexibility of the nervous system , learning and adaptability of the animal. With the increasing complexness of the organism, the gene pas seul of all mechanism are slight likely to lead to a liberalist change. The vast circumstance they lead to simplification in the viability of the organism. In this regard, keeping species range becomes one of the most important conditions for its survival.