Terms to know Flashcards
Parasitology
study of parasites and their relationship to their host
Phoresis
“Living together” - close interrelationship between 2 different organisms for long periods of time
Mutualism
both benefit; usually obligatory; physiologic dependence
Commensalism
one partner benefits; host is not affected
Parasitism
one either harms its hosts or lives at the hosts expense
Dead - end or incidental hosts
do not develop high levels of the parasite in their system and cannot pass the pathogen on to other organisms
Hyperparasitism
a parasite that is a host to another parasite
Abberant
animal that is not the normal host of the parasite it is harboring
Direct life cycle
parasite completes entire life cycle in one host species
indirect life cycle
more than one host species is required to complete life cycle
Ectoparasites
found on (not in) host
Endoparasites
found internally in host
Facultative parasite
“opportunist” - not normally a parasite (does not require a host to survive) but will become a parasite if opportunity arises
Obligate parasite
all or part of the life cycle must be a parasitic relationship with a host
incidental (exotic) parasite
normal host is a different species
Definitive host
harbors sexual (mature) stages of parasite; if parasite undergoes sexual reproduction, it will occur in this host
Intermediate host
required in life cycle of parasite; parasite undergoes some development in this host
Paratenic or transport host
no parasite development in this host, but parasite remains alive and infective for another host (sort of a parasite “fail-safe” plan to continue its existence)
Reservoir host
a host that serves as a source for the parasite to be transmitted to the usual host
Biological vector
essential to the life cycle completion of the parasite. Parasite must undergo some of its life cycle in this vector
Mechanical vector
vector is not required in life cycle of parasite; vector physically transfers infective stage of parasite to new host
Sylvan cycle
a parasite cycles through its life cycle among wild animals normally
Urban cycle
a parasite cycles among domestic animals. easy for man to get included in this cycle
Etiology
the cause of a disease
Pathogenesis
the processes involved in the development of the disease
Amastigote
kinetoplast and kinetosome above the nucleus, flagellum short and confine in pocket. cell is globular
Promastigote
kinetoplast and kinetosome at anterior end of cell, flagellum free and lone. cell is elongated
Epimastigote
kinetoplast and kinetosome close and anterior to the nucleus. there is a short undulating membrane before the flagellum emerges at the anterior of the cell.
Trypomastigote
kinetoplast and kinetosome at posterior end of cell. flagellum forms an undulating membrane that runs the length of the cell and may continue free when it reaches the anterior cell. cell is elongated
Polyembryo
Development of many offspring from a single zygote
Internal budding
New individual grows from somatic tissue of parent
Schizogeny
(multiple fission)
produces many daughter cells
Binary fission
Mitotic division of 1 cell into 2
Monoecious
(hermaphroditism)
Single individual possesses gonads of both genders
Dioecious
Each individual is a separate gender
Katayama syndrome
severe reaction to eggs, fever, chill, abdominal pain, cough
Clay pipestem fibrosis
portal vein surrounded by granulomas
Rostellum
fleshy protuberance of the scolex of a tapeworm, which may or may not bear hooks
Arrested Larval development
larvae undergo no further growth and have a slow metabolic rate
Halzoun syndrome
Attachment of the adult pentasomes to nasopharyngeal tissues; causes pharyngeal discomfort, paroxysmal coughing, sneezing, dysphagia, and vomiting
Extrinsic incubation period
time interval between infection of vector and first transmission of pathogen by vector
Transovarial transmission
infection of eggs in ovaries of an infected female vector leading to new vector infection (“vertical transmission”)
“Dead-end” hosts
host that does not develop high titer of pathogens
