Igazi ke lihamba ngolu hlobo: liqala entliziyweni→liye kunothumela-→liye kwimithanjana kanothumela→liye kwi-capillary→liyekumthanjana omncinane kanobuyisa i-venule→liye koonobuyisa→ ligqibele entliziyweni. Oku ke kukujikeleza kwegazi emzimbeni okubizwa ngokuba yi-circulation ngesiNgesi. Zimbini ke iintlobo zee-circulations kule nkqubo yokujikeleza kwegazi ebizwa ngokuba yi-circulatory system ngesiNgesi. Eyokuqala yi-systemic circulation yindlela elihamba ngayo igazi kumalungu omzimba amaninzi. Eyesibini inkqubo yi-pulmonary circulation yindlela igazi elityhutyhatyhutyha ngayo nge-miphunga. (I-Pulmonary iththa ukuthi ¨okumalunga nemiphunga¨). Igazi lisebenza kanje ke kwizilwanyana ezanyisayo, kuquka nabantu. Le nkqubo yokujikeleza kwegazi emzimbeni iyohluka kwezinye izilwanyana ezinethambo lomqolo ngandlelana ithile. Izilwanyana ezingenalo ithambo lomqolo zahluke kakhulu ke zona.