A tapeworm is a type of parasite that lives in the intestines of its host. It lacks a digestive system of its own and relies on its host for food. The tapeworm absorbs the nutrients and other substances it needs to survive through its body surface. This means that it does not take in food through its mouth, and the scolex (the head of the tapeworm that contains hooks and suckers) is mainly used for attachment to the host's intestine.