Briefly explain 1 feature that distinguishes Cnidaria from Platyhelmenthes. In a half page or less, Explain how a metanephridium works.
Examples are sponges, worms, dogs, birds, fish.
It s a living organism that moves, reproduces, and has physiological functions. It breathes oxygen and goves of CO 2 . It has a musculoskeleton system and internal organs, like an elephant or mouse. In Cnidaria gas exchange is through water being pumped in and out of the gastrovascular cavity. Within the gastrovascular cavity circulation is performed by taking in and expelling water.