sessile
Sponges come in a variety of shapes and sizes. For example, they may be shaped like tubes, fans, cones, or just blobs. They range in diameter from about a centimeter 0.4 inches to over a meter 3.3 feet . Many species live in colonies that may be quite large. Adult sponges are sessile . This means they are unable to move from place to place. Root-like projections anchor them to solid surfaces such as rocks and reefs.