unit 2: parasitism

the negative relationship between 2 different species: the host and the parasite

"heterotypic, negative, temporal or permanent, external or internal association, among a species, the parasite (usually smaller and with a lower zoological level) and the host (bigger and higher level)"

define parasitism

parasite

which is smaller, the host or the parasite?

parasite

which is less evolved/developed, the host or the parasite?

host

which suffers, the host or the parasite?

1. definitive host (DH)/ final host (FH)

2. intermediate host (IH)

what are the 2 types of hosts regarding the stage of the parasite that it harbors?

the host that harbors the adult stage of the parasite, with sexual production

what is the definitive/final host?

definitive/final host

what is the name for the host that harbors the adult, sexual stage of the parasite?

the host that harbors the immature stages of the parasite with asexual reproduction

what is an intermediate host?

intermediate host

which type of host harbors the immature/asexual parasite?

the host where the parasite species was described for the first time

what is the "type" host?

the main, most specific host for the parasites that affect a broad host range

what is the "principal" host?

a very specific species that is essential for the parasite's life cycle

what is the "obligatory" host?

not the usual host, although it is sometimes parasitized

what is the "accidental" host?

accidental host

if a human eats a parasitized fish, what type of host is it?

a host that is not necessary for the parasite's life cycle, but eases parasite transmission

what is a "paratenic" host?

a host that is infected only in artificial/laboratory conditions

what is an artificial host?

paratenic host

although fish are not necessary for the life cycle of an anisaki (parasite), they help to spread the parasite when eaten by a cetacean. what type of host is the fish?

obligatory host

to develop throughout their life cycle, Fasciola (parasite) need to infect aquatic snails and develop inside of them. what type of host is the aquatic snail?

an invertebrate that carries a parasite to the definitive host

what is a vector?

a vector that only transports the parasite, the parasite does not develop inside of the vector

what is a mechanic vector?

a vector that carries the parasite but also harbors its development

what is a biological vector?

1. multiplicative- parasitic multiplication occurs inside of the vector

2. cyclovolutive- the parasite evolves inside of the vector

3. cyclomultiplicative- the parasite both multiplies and evolves inside of the vector

what are the 3 types of biological vectors?

mechanical vector

what is the type of vector called that only transports the parasite- the parasite does not develop inside of it?

biological vector

what type of vector both transports and harbors the parasite's development?

multiplicative vector

what type of biological vector harbors multiplication of the parasite?

cyclovolutive vector

what type of biological vector harbors evolution of the parasite (throughout its life cycle)?

cyclomultiplicative vector

what type of biological vector harbors both multiplication and evolution of the parasite?

an animal that harbors a parasite but does not suffer, only contributes to its spreading

what is a reservoir?

a host acting as a connecting to different biological cycles of the parasite

what is a bridge?

a bridge

rats connect trichinella to its domestic cycle in pigs and its sylvatic cycle in wild boars. because it connects these 2 different biological cycles, what is the rat called?

a parasite that infects plants

what is a fitoparasite?

zooparasites

what is the name of parasites that infect animals?

1. protozoa

2. helminths (plathelminthes, nemathelminthes, acanthocephalams, annelids)

3. arthopoda (arachnids, insects)

what are the 3 classes of zooparasites?

flat

plathelminthes are _____ worms

cestodes (segmented)

trematodes (unsegmented)

what are the 2 types of plathelminthes?

nematodes

what type of nemathelminthes do we study?

round

nemathelminthes are _____ worms

insecta, arachnida

what are the 2 types of arthropoda?

ectoparasites

what type of parasites live outside of the host?

arthopods, monogenea

what are the 2 classes that are ectoparasites?

parasites that live outside of the host

what are ectoparasites?

parasites that live inside of the host

what are endoparasites?

coelozoics- live in coeloma

histozoics- live in tissues

citozoics- live in cells

plasmazoics- live in cytoplasm

what are the 4 classes of endoparasites?

one that is living outside of its usual place

what is an erratic parasite?

a parasite that needs the host to complete the lifecycle

ex: hypodermal parasites need to lay their eggs under the host's skin so they can hatch

what is an obligated parasite?

a parasite that does not rely on the host for most of its life cycle

what is a facultative parasite?

a parasite that prefers not to be a parasite

ex: musca prefers to live in trash or on feces, but can live off an animal

what is an accidental parasite?

the parasite can affect a wide range of hosts

what does eurixenic mean?

one that cannot affect many hosts

what is a stenoxenic parasite?

oligoxenic

what is a parasite that can affect only a few hosts called?

monoxenic

what is a parasite that can only affect one host species called?

monoxenic

if a parasite only affects one host in their life (the DH), what is it called?

a parasite that requires one DH and one IH to complete its life cycle

what is a heteroxenic parasite?

a parasite whose host can act as both the IH and DH

what is an autoheteroxenic parasite?

a parasite that can make disease

what is a pathogenic parasite?

no, very few are pathogenic

because they do not want to kill the host, as they support their life

are many parasites pathogenic?

parasites that only promote disease in some situations

what is a facultatively pathogenic parasite?

yes, most are

are many parasites facultatively pathogenic?

a parasite that cannot make disease in the host

what is a non pathogenic parasite?

no, very few are

are many parasites non pathogenic?

temporary or permanent

regarding the length of the stay of the parasite in the host, it can be what 2 options?

constant

if the parasite stays in the host during its entire life, it is called....

periodical

if the parasite stays in a host during only part of its life, it is called....

one that is parasitic only during its adult stages

what is an imaginal parasite?

one that is parasitic only during its larval stages

what is a protelic parasite?

imaginal

if a parasite only infects hosts during its adult life, it is called...

protelic

if a parasite only infects hosts during its larval life, it is called...

the parasite only requires one type of host in their life cycle

what is a direct life cycle?

monoxenic parasites

what type of parasites have a direct life cycle?

DH only

in a direct life cycle, does the host infect IH or DH?

the parasite requires more than one host in their life cycle

what is an indirect life cycle?

indirect

what type of life cycle involves a IH- direct or indirect?

heteroxenic parasites

what type of parasites have an indirect life cycle?

diheteroxenic

what type of heteroxenic parasite has 1 DH and 1 IH?

1 DH

2 or more IH

a poliheteroxenic parasite has ___ DH and ____ IH

diheteroxenic- it only has 1 IH and 1 DH

is this parasite, Faciola hepatica, diheteroxenic or poliheteroxenic?

poliheteroxenic- it has 2 IH and 1 DH

is this parasite, Dicrocoelium dendriticum, diheteroxenic or poliheteroxenic?