Very long and large organic molecules called are made of small units called
. Examples of the small units include sugars, which combine to form
; nucleotides, which form
; and amino acids, which form

fumikage isn't really a bird, and tsuyu does have teeth. tsuyu has a transformation quirk which still allows her to be partially human. otherwise we'd have a large frog running around. fumikage has teeth because again, he isn't a bird. his head was a quirk mixture if i'm correct.