In a parasitic relationship, the host is the organism that is harmed or exploited by the parasite.

Mesoparasite is not a type of parasite. Endoparasites live inside the host's body, ectoparasites live on the host's body, and hyperparasites parasitize other parasites.

The trophic stage is the stage of a parasite's life cycle when it is inside the host and obtaining nutrients from the host.

Tapeworms are endoparasites that live inside the digestive tract of their hosts.

The infective stage is the stage of a parasite's life cycle when it is outside the host and capable of infecting a new host.

Lice are ectoparasites that live on the skin of their hosts.

A hyperparasite is a parasite that parasitizes another parasite.

Ichneumon wasps are hyperparasites that parasitize other insects.

Parasitism is the relationship between a parasite and its host, in which the parasite benefits and the host is harmed.

Mycorrhizae are fungi that form a mutualistic relationship with plants, helping them to absorb nutrients from the soil.

Commensalism is the relationship between two organisms in which one benefits and the other is neither harmed nor benefited.

Epiphytes are plants that grow on trees, using them as support but not harming them.

Amensalism is the relationship between two organisms in which one is harmed and the other is neither harmed nor benefited.

Penicillium is a fungus that produces antibiotics that kill bacteria.

The three main types of parasites are endoparasites, ectoparasites, and hyperparasites.