Introduction
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A vertebrate is an animal with a skeleton on the inside of it body. The word comes from vertebrae, the bones that make up spines.
Animal which are not vertebrates are called invertebrate. There are five classes of vertebrates. They are: Amphibians, mammals, birds, reptiles and fish.
Examples of vertebrates are mammals, birds, and fish. Sharks, and related skates and rays, are vertebrates with cartilage instead of bones.