Otu ntụzịaka na-atụgharị bọọlụ nwere otu igwe na-asachapụ ihe abụọ (ihe na-asa mmiri na ebe a na-asa ụlọ) na otu oghere nwere bọọlụ. Ha nwere ike ịkwado ibu axial n'otu ụzọ. Otu oghere nwere bọọlụ ndị ahụ ebe igwe na-asa akwa na-edozi oche na-eduzi ha.
