Parasitism is a relationship in which one species benefits, while the other does not (unlike mutualism type of symbiosis). In case of parasitic plants, the parasite lives off of the host plant and obtains its nutrients and water from the host plant itself. An example of parasitic plant is Cuscuta sp., commonly known as Dodder. These are parasitic vines and are attached to their host through haustoria, small rootlike structure that allows it to bind itself to host plant, and directly obtain their nutrients, minerals and water from the host's vascular system. Another example of parasitic plants is juniper mistletoe or Phoradendron juniperinum. This plant lives off California juniper or Juniperus californicai. This parasitic plant covers the host plants to such an extent that it appears to be a part of the host. It is more commonly found in California, United States.
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