Most alcyonacean corals do not make full-body, protective skeletons like the corals that build reefs. Their bodies are instead supported by separate skeletal pieces (sclerites) embedded in their flesh. While some Alcyonacea are called soft corals, the hard sclerites give their flesh a bumpy or spiky texture. Some grow in a globular, mushroom-like shape, but others (sea fans) have many, flattened branches that intertwine to form a lattice. The branching species get additional support from binding materials (such as proteins or calcium carbonate). This loose structure makes their bodies strong enough to grow as tall as several meters, while remaining flexible enough to sway in ocean currents. Many Alcyonacea release toxic chemicals, such as terpenes, that function in defense. Their often bright-colored bodies are a warning to predators that, between the toxins and the sclerites, they are not good to eat.