Cikin buroki wani karamin jini ne da ke fitowa daga gajiyar thoracic, wanda shine babban jijiya na kirji. Yana ba da jini mai iskar oxygen zuwa buroshi (bututun da ke ɗaukar iska zuwa huhu) da sauran sifofin huhu, irin su bronchioles, ƙwayoyin haɗin gwiwa, da jijiyoyin bugun jini. Jijiyoyin bunchial yana da mahimmanci ga iskar oxygen da abinci mai gina jiki na huhu, kuma yana taka rawa wajen amsawar rigakafi da sarrafa kumburi a cikin huhu.