chapter 2 lesson1 simple invertebrates

Animals that do not have backbones are invertebrates. The simplest invertebrates is the sponge. This sponge is not the kind in your house. Living sponges are found on the ocean floor. They don't move. If a part of the sponge is damaged the cells of the sponge regrow it. This growth is called regeneration. All sting celled animals like the sting ray live in the ocean. Flatworms have long, soft,and flat bodies. If a part of a flatworm was damaged the cells would regrow the part like the sponge. Some flatworms are scavengers. Scavengers feed on organisms. I love the ocean. Maybe I'll study more ocean animals when I grow up.