Agnatha Current Affairs, GK & News

Difference Between Agnatha and Gnathostomata

With currently 64000, species, majority of the members of Phylum Chordata belong to sub-phylum Vertebrata. All vertebrates possess notochord during the embryonic period only and later it is replaced by bony vertebral column. Further, the vertebrates have a ventral muscular heart with two, three or four chambers, kidneys for excretion and osmoregulation and paired appendages ..