Enwere ike iji ihe nchọpụta okpomọkụ kwụ ọtọ mee ihe n'ebe siri ike. Sistemụ a nwere njirimara nke mgbanwe siri ike na arụmọrụ dị elu. A na-eji ya eme ihe nke ukwuu n'ọrụ ụlọ ọrụ mmepụta ihe na azụmahịa.