Parasitology

Question 1

Definitive host

Answer 1

Final life cycle

Reproduce here

Question 2

Intermediate host

Answer 2

Go through multiple cycles/stages before transmitted to the definitive host

Question 3

Paratenic host

Answer 3

Transport

No development here, just carrier

Question 4

Mechanical vector

Answer 4

Carries part from animal to animal

Ex: horsefly

Question 5

Prepatent period

Answer 5

Time from final definitive host to pick up and go through the life cycle

Can see diagnostic traits, ex: tapeworms (eggs in feces)

Question 6

Patent period

Answer 6

Once eggs in feces, dx stages in feces

Once stops prepatent over

Question 7

3 types of parasites

Answer 7

Protozoans

Helminths

Arthropods

Question 8

Protozoans

Answer 8

Amoebas, ciliates, flagellates, and apicomplexans

Question 9

Helminths

Answer 9

Worms

Platyhelminths, nematodes and acanthocephals

Question 10

Arthropods

Answer 10

Insects, acarines, pentastomes, Crustacea

Question 11

Symbionts

Answer 11

Living together

Question 12

Phoresis

Answer 12

Traveling together

Question 13

Commensalism

Answer 13

1 benefits and other is neither helped nor harmed

Question 14

Obligate parasite

Answer 14

Cannot live without host, no free living stages

Ex: round worm, tick and mosquito

Question 15

Facultative parasite

Answer 15

Can use matter and garbage to complete life cycle

Question 16

Hyperparasitism

Answer 16

Parasite infecting parasite

Larval heartworm is a hyperparasite of mosquito- parasitizes develops

Question 17

Parasitiasis

Answer 17

Infected but no outward signs of disease

Question 18

Parasitosis

Answer 18

Outward signs of disease

Question 19

Sylvatic cycles

Answer 19

Involve parasites of wild animals infecting humans

Question 20

Urban or domestic cycles

Answer 20

Involve parasites of companion or food animals or domestic rats for cross over

Question 21

Evolution

Answer 21

Parasites co evolved with host are less likely to be pathogenic

If recently colonized are more pathogenic, result of keeping animals in environment not well adapted to

Question 22

Overdispersion

Answer 22

Not all animals harbor the same number of parasites and the level can vary

Question 23

How to escape immunity

Answer 23

Molecular mimicry

Antigenic variation

Secretion of substance

Question 24

Molecular mimicry

Answer 24

Mimic linear amino acid epitopes of the host

Plasmodium

Question 25

Antigenic variation

Answer 25

Trypanosomes express new surface glycoproteins eluding destruction by the host

Question 26

Secretion of substances

Answer 26

Block IgM so cytokine secretion is impaired

Ex: entamoeba evades humoral immunity by degrading Ab via proteases

Question 27

Harmful effects of parasites

Answer 27

Suck blood, feed on solid tissue, compete with host for food, cause mechanical obstruction, cause pressure necrosis, destroy host cell via asexual repro and rupture cells, produce toxins, cause allergic response, cause host reactions to foreign body, stimulate neoplastic transformation of cells, carry disease and other parasites and reduce host resistance

Question 28

Increase fecundity

Answer 28

Produce large number of eggs or cysts

Hermaphroditism and asexual repro

Infected IH more susceptible to ingestion by DH

Question 29

Getting to host

Answer 29

Oral, infest, intermediate host, transmammary, transplacental, vector borne and skin penetration

Question 30

Staying in place

Answer 30

Hooks 
Flukes- oral sucker 
Thorny 
Mouth 
Spines

Question 31

Euryxenous

Answer 31

Infect wide variety of hosts

Question 32

Stenoxenous

Answer 32

Host specific