Vertebrates are animals that have a back bone. These animals include humans, dogs, cats, pigs, cows, and chickens.
The backbone is also called the spine and is made of bones called vertebrae.
You can bend forward, left and right, and some of you can bend backwards (doing a back bend). This is because your backbone can bend.
To find out why your backbone is so flexible as well as how to make a backbone model, see BACKBONE.