PARASITOLOGY - SYMBIOSIS

Symbionts

Organisms that are very closely associated with another, usually larger, organism (host). Can live on, in or sometimes very near to its host

Ectosymbionts

Attached to the outside of the host

Phoresis

Exists when two symbiotes are merely “traveling together” E.g. bacteria on a fly’s legs

Endosymbionts

Within the body of the host

Phoresis & commensalism

loose association

Mutualism & parasitism

intimate association

Commensalism

Occurs when one membe r of the associating pair, usually the smaller, receives all the benefits and the other member is neither benefited nor harmed

Facultative

both species are capable of living independently from one another

Obligate

one must live in association with its partner

Mutualism

Occurs when each member of the association benefits the other ● Mutuals are metabolically dependent o n one another, one cannot survive in the absence of the other