Chotupa cha choluka chimakhala kutentha komanso chinyezi, ndipo chitha kugwiritsidwa ntchito ngati chogwiritsira ntchito mosamala. Amagwiritsidwa ntchito makamaka pakuchira ndi chithandizo chathanzi. Itha kukhala ndi chida chotumizira oxygen kuti ipereke kwa nyama.