No matter where you live, you can get a parasite. Whether or not you become infected with parasites depends on where you spend your time, what kind of work you do, what kinds of food you eat and how you prepare your food. Parasites live all over the world but they cannot live alone. Parasites must have a host. A host is another living thing that the parasite either lives inside of or on. For example, ticks live on hosts such as deer, rabbits and dogs. Parasitic worms live inside hosts such as fish, birds and mammals. As long as there are animals and plants in an environment to act as hosts, there will also be parasites. This is a diagram of the life cycle of a tapeworm. It is an endoparasite. That means it lives inside of its host. Follow the life cycle of the tapeworm. Identify the host(s). A) cow B) grass C) cow and grass D) cow and human