Invertebrates

Hello I'm going to tell you tell you about invertebrates. Invertebrates have no backbone. A sponge is a invertebrate. And I'm not talking about a house sponge. I'm talking about a sponge that lives at the ocean. If the sponge is damaged it will grow back it's called regeneration. Did you know that flatworms live inside of animals? A flatworm is more complex than sponges and sometimes sting-celled animals. A roundworm is another type of worm and is even more come complex than a flatworm. One type of roundworm lives in pigs. Well that is all for now. Bye.