Question

Unlike non-vertebrate chordates who breath cutaneously, most derived vertebrates have specialized structures for respiration. Why? What's the reason?

Answer 1

Most of the derived vertebrates have specialized structures for respiration because the oxygen requirement of the derived vertebrates is far more than that of the non vertebrate chordates.Also, most of the derived vertebrates are very large and it becomes difficult for each cell to interact with the environment directly for process of diffusion.The process of specialized structures therefore help the derived vertebrates for the process of diffusion.