Fill in the Blanks Respiration, nutrition and reproduction of vertebratesOnline version Repaso de cómo se alimenta, respiran y se reproducen los vertebrados by Cris Fernández 1 a ) Mammals , reptiles and birds get oxygen from the . They breathe with b ) Fish use to get oxygen from the . c ) Mammals are bord directly from their mother . They are d ) Birds , reptiles , amphibians and fish reproduce by laying . They are e ) Most vertebrate animals are ( they eat both animals and plants ) or ( they eat other animals ) f ) Some mammals and a few birds are , they only eat plants .