Why Do Spiders Have Exoskeletons?
Spiders do not have a hard internal skeleton. Instead, they have a rigid, external skeleton that protects their body. It consists of chitin, which is a protein compound that is pliable. In addition, spiders also have a cuticle.
The cuticle contains multiple layers of chitin, proteins, and wax. It provides support and helps keep the spider from drying out. However, it has a serious drawback: it cannot expand like human tissue.
When spiders molt, they release hormones that initiate a series of processes. As a result, they are able to expand their body and grow larger. Before the process begins, a young spider must climb out of its old shell. This process is known as ecdysis.
After ecdysis, a new exoskeleton grows on the inside of the old one. To do this, the spider must first crack the shell. Once the old one is cracked, the spider secretes a molting fluid that enables it to pull its legs out of the exoskeleton.
After the fluid is released, the spider stretches the new exoskeleton into a soft form. It then starts to harden. If the molting process is done incorrectly, the spider may die or lose limbs.
A spider’s exoskeleton is made up of a rigid, outer layer and an elastic, inner layer. The outer layer remains intact until the exoskeleton is ready to be shed.
As a result, spiders must molt periodically. Some species of spiders molt once a month or year. Others molt throughout their lives.