Vertebrates vs. Invertebrates
Being a vertebrate means that you have a backbone, or spinal nerve chord. When we think of life forms that are vertebrates, we can usually come up with a numerous list of creatures. However, of all beings found in the Animalia kingdom, only about 5% of them are considered Vertebrates. Invertebrate animals consist of creatures such as, but not limited to: sponges, polyps, jellyfish, insects, roundworms, and mollusks. Sponges maintain their stiff structures by specialized cells known as Spicules; mollusks keep their shape by the use of hard external shells. These will be mentioned later...