obligate parasite

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Related to obligate parasite: accidental parasite


1. a plant or animal that lives upon or within another living organism at whose expense it obtains some advantage; see also symbiosis. Parasites include multicelled and single-celled animals, fungi, and bacteria, and some authorities also include viruses.Those that feed upon human hosts can cause diseases ranging from the mildly annoying to the severe or even fatal. (See accompanying table.)
Types of parasites.
adj., adj parasit´ic.
accidental parasite one that parasitizes an organism other than the usual host.
facultative parasite one that may be parasitic upon another organism but can exist independently.
incidental parasite accidental parasite.
malarial parasite Plasmodium.
obligate parasite (obligatory parasite) one that is entirely dependent upon a host for its survival.
periodic parasite one that parasitizes a host for short periods.
temporary parasite one that lives free of its host during part of its life cycle.

ob·li·gate par·a·site

a parasite that cannot lead an independent nonparasitic existence, in contrast to facultative parasite.

obligate parasite

See parasite.

ob·li·gate pa·ra·site

(ob'li-găt par'ă-sīt)
A parasite that cannot lead an independent nonparasitic existence, in contrast to facultative parasite.
References in periodicals archive ?
Obligate parasite A parasite that requires certain hosts to develop and cannot live apart from their host.
This finding fits with the obligate parasite conjecture.
Viruses are obligate parasites of living cells, he says; every living organism in the biosphere suffers viral parasitism, and its genome bears the indelible imprint of virus infection.
Eggs usually hatch at the end of autumn, and new mites, which at their larval stage are obligate parasites of warm-blooded hosts, usually feed and grow on the skin of small rodents and dogs, injecting lytic enzymes to digest cutaneous cells.
Equine babesiosis is caused by Babesia equi (Theileria equi) and Babesia caballi, which are intracellular obligate parasites of the phylum Apicomplexa and cause hemoparasitic disease in horses [2,3].