moults, Arthropods

Arthropods (Phylum Arthropoda, from Greek ἄρθρον arthron, “joint”, and ποδός podos, “foot”) are the largest phylum of animals and include the insects, arachnids, crustaceans, and others. Arthropods are characterised by the possession of a segmented body with appendages on at least one segment. They have a dorsal heart and a ventral nervous system. All arthropods are covered by a hard exoskeleton made of chitin, a polysaccharide, which provides physical protection and resistance to desiccation. Periodically, an arthropod sheds this covering when it moults.