Umubiri wongera kandi gukenera umunyu mu mikorere y’imyakura no mu mikorerere myiza y’inzira zijyana ubutumwa ku bwonko. Aha gatatu umunyu wongera gukenerwa mu mubiri ni mu mikorere myiza y’inyama zitwikiriye amagufwa. Umunyu wo mu gikoni uba ugizwe n’umunyu ngugu wa sodiyumu (Na+) n’uwa chlore (Cl-).