Parasitic Modes of Life Flashcards
define Commensalism
relationship between two species which may benefit from but do not depend on one another
define Phoresis
transport and shelter with no metabolic interactions
define inquiline species
“house guest” - exploits the living space of another species
define Mutualism
association where both species gain benefit but the association is not obligatory
define symbiosis
relation between species - can be divided into intra- and interspecific forms
define Parasitoid
intermediate stage between predation and true parasitism - attach themselves to a host, consuming and eventually killing it
define Facultative parasitism
can survive as free-living forms but can also become fully functional parasites
define Obligate parasite
parasite must find a receptive host in order to complete their life cycle
define temporary/periodic parasite
parasite infect for short periods and verges on predation (inc. parasitoids)
define permanent parasite
parasite remains with their host until they have completed the appropriate stage in their life cycle
define Larval parasite
has a parasitic junenile stage
define Hyperparasite
parasite of parasites
define Microparasite
small parasite with short generation times, life spans shorter than host. Often provoke strong immune responses from vertebrate hosts
define Macroparasite
generally do not multiply within or on their hosts and have relatively long generation times. Normally induce little to no host immune response, but cause weakening to produce morbidity (not mortality)
define Mean Worm Burden (MWB)
Number/severity of macroparasites a host can tolerate without producing an immune response
define Direct life cycles
those where there is a single host, e.g. with a parasitic adult form and free-living larval stage
define Indirect life cycle
those with several hosts with particular roles throughout a parasitic life history
define Accidental host
species not notmally part of the parasite life cycle but in permissive forms the parasite is able to complete its life cycle. In non-permissive forms the parasite fails to develop and dies within the host
define Paratenic host
host that ingests larval stages and carries them in a form of arrested development, accumulating them until they have a chance of infecting a definitive host (also called transport hosts)
define Definitive host
host in which sexual reproduction takes place
define Intermediate host
asexual phase of the life cycle but often represent a multiplication stage
define sacculinisation
evolving to lack sensory structures and motility because such functions are largely redundant - mostly seen in endoparasites