Definition of level of a metabolism Urea. R.Gejdengajnom has been developed operation isolated желудочка which gave the chance to receive pure gastric juice. But this operation did not consider topography of nerves, иннервирующих a stomach. At formation isolated желудочка nerves were cut, and желудочек it appeared денервированным. This method it was possible to study only гуморальную a phase of gastric secretion. I. P.Pavlov, having considered lacks of a technique of R.Gejdengajna, has offered a way of operation isolated желудочка without перерезки nerves, иннервирующих a stomach that has given the chance to study gastric secretion throughout all period of digestion. In fauna there are some basic ways of reaction to external temperature. At пойкилотермных (холоднокровных) animals whom concern the majority беспозвоночных and the lowest позвоночных, body temperature depends on ambient temperature. Intensity of power processes and activity level пойкилотермных organisms are defined by environment temperature (fig. 27).