An exoskeleton serves for protection on the organism. This structure is essentially an exterior skeleton that also offers support to the body. A blue crayfish is pictured. This type of crayfish has a flexible exoskeleton composed of polysaccharides (chitin), which offers it extra support and protection. This exoskeleton; however, frequently sheds as the crayfish grows, five to six times a year to be exact. This process makes the crayfish weak and more susceptible to predators. During the first week of molting, the new emerging shell is very weak, but it later hardens as time progresses.