Parasite In the relationship known as parasitism, the partner gains benefit, always smaller, is the parasite which to some degree injures its partner and the other to be injured at the same time is known as the host Parasites(animal parasites) are invertebrates that can not live independently and should depend upon others to maintain their lives(live at the expense of others) s vo0 多sParasite — In the relationship known as parasitism, the partner gains benefit, always smaller, is the parasite which to some degree injures its partner and the other to be injured at the same time is known as the host. — Parasites (animal parasites) are invertebrates that can not live independently and should depend upon others to maintain their lives (live at the expense of others)