Obwongo bufulumya sigino z’amasannyalaze (electrical signals), ezikolera wamu n’okutomeggana kwa kemiko (chemical reactions), okusobozesa ebitundu by’omubiri okukolagana (okuwuliziganya). Obusimu (nerves) bwe busindika sigino zino wonna mu mubiri. Okutwalira awamu, emigaso gy’obwongo mulimu: