Ebantwini, laa magumbi mane azii-atria ezimbini nee-ventricles ezimbini. I-Atria ithetha ngamagumbi amabini; ibe yona i-atrium s talking about two chambers; atrithetha ngegumbi elinye. kukho i-atrium yangasekunene ne-ventricle yangasekunene. La ke ngamagumbi afumana igazi elivela entliziyweni. Ngawo la ampompa igazi elimpompela emiphungeni. Lisakufika emiphungeni igazi ligqitha nge-oksijini lize lishiye i-carbon dioxide. Eli gazi livela emiphungeni naloo lisiya kungena kwi-atrium nakwi-ventricle zangasekhohlo. Zona ke ezi atrium ne-ventricle zilikhuphela ngaphandle eli gazi lohlukane nomzimba. I-ventricle yangasekhohlo isebenza ngamandla ngokuphindwe kathandathu kune-ventricle yangasekunene kuba ithwala igazi eline-oksijini.