Tick and dog share a symbiotic relationship that can be described as parasitic. Symbiosis is the relationship between two organisms, where either one or both the organisms get the benefit. In mutualism, both the organisms benefit from the relationship, while in parasitism, only one organism gets the benefit, while the other gets adversely affected. In case of tick living on a dog, tick is a parasite. It is an invertebrate that bites the animal skin and buries its head into the animal skin and then it sucks their blood. Here, the tick is living off the dog by consuming its blood. The dog, on the other hand, loses blood and may also be infected by other diseases and hence gets adversely affected. Thus, tick living on a dog represents parasitic symbiosis.
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