All vertebrates possess

Vertebrates have a ventral muscular heart with two, three or four chambers and, kidneys for excretion and osmoregulation. Paired appendages (fins or limbs) are present only in gnathostomes; absent in agnathans. Pisces possess fins while tetrapods possess limbs. Limbs are absent in some tetrapods like Ichthyophis (Amphibia) and snakes (Reptilia). Jaws are absent in agnathans. Some gnathostomes too lack teeth (e.g., birds and turtles). Lungs are present in tetrapods but  absent in Pisces, which respire by gills.