acrania



acrania defined in 1951 year

acrania - acrania (cephaloghordata);
acrania - Sub-phylum of Ghordata containing only species of amphioxus, all marine. Unlike Vertebrata they have no brain, skull, or cartilaginous or bony skeleton; but they have typical chordate dorsal tubular nerve-cord with double nerve roots, notochord, gill-slits, muscle blocks (myotomes); and they have an unexpected feature, found in no other chordate though in many invertebrates - nephridia as excretory organs. They may be closely related to early ancestors of fish and other vertebrate groups. A very early fossil probably belonging to the group has been discovered (Jaymoytius from the Silurian).

near acrania in Knolik


acquittancehome
letter "A"
start from "AC"
acrasiales

definition of word "acrania" was readed 5293 times

Legal info