Definitions: Exam 1

Question 1

Direct life cycle

Answer 1

single definitive host, no intermediate host,

Question 2

Indirect Life Cycle

Answer 2

one or more intermediate host in addition to definitive host

Question 3

Symbiosis

Answer 3

living together

Question 4

Commensalism

Answer 4

one benefited, other neutral no harm or benefit

Question 5

Mutualism

Answer 5

both benefit, usually obligatory, cannot survive without the other

Question 6

Phoresis

Answer 6

traveling together, no physiologic or biological dependence

Question 7

Obligatory parasites

Answer 7

cannot complete lifecycle without host

Question 8

Facultative parasites

Answer 8

not usually parasitic but can become so if accidentally eaten or enter a wound or other orifice

Question 9

Accidental parasites

Answer 9

do not survive in the wrong host

Question 10

Temporary or intermittent parasites

Answer 10

visits the host from time to time for food.

mosquitoes, bed bugs

Question 11

Definitive host

Answer 11

parasite reaches sexual maturity, often vetebrates

Question 12

Intermediate host

Answer 12

needed for development, sexual maturity not reached

Question 13

Paratenic host

Answer 13

bridge ecological gap, no development but parasite stays alive

Question 14

Reservoir host

Answer 14

a host which allows the pathogen to live, and possibly grow, and multiply.

animal harboring that can be transmitted to humans

Question 15

Zoonoses

Answer 15

a disease which can be transmitted to humans from animals.

Question 16

Apicomplexans

Answer 16

Have an apical complex, can bore into host cell

Question 17

Trophozoites

Answer 17

Active, feeding, multiplying stage
In parasitic species this is the stage usually associated with pathogenesis

Question 18

Cysts

Answer 18

are stages with a protective membrane or thickened wall

common in organisms that may encounter harsh conditions

Cysts that must survive outside the host usually have more resistant walls than cysts that form in tissues

Question 19

Specific gravity

Answer 19

the density of that object divided by the density of water.

necessary in fecal floatations

Question 20

Media

Answer 20

have to choose media with proper specific gravity

Question 21

Sheather’s sugar

Answer 21

specific gravity of 1.27

enough to float any ova

Question 22

Excystation

Answer 22

The stage in the life cycle of a parasite in which it escapes from a cyst (after being swallowed by its host)

Question 23

Encystment

Answer 23

the formation of a cyst. The process of becoming enclosed by a cyst.

Question 24

Encystment

Question 25

Prepatent period

Answer 25

the period between infection with a parasite and the demonstration of the parasite in the body especially as determined by the recovery of an infective form (as oocysts or eggs) from the blood or feces. | before symptoms

Question 26

Flagellates

Answer 26

a cell or organism with one or more whip-like appendages called flagella

Question 27

Sporulated oocysts

Answer 27

The process by which immature (noninfective) coccidian oocysts develop into the mature, infective form. ## Footnote resistant to adverse environmental conditions and can survive as long as one year in moist, protected environments

Question 28

Percutaneous

Answer 28

Infection via skin penetration

Question 29

Transmammary

Answer 29

Arrested larvae can become reactivated during parturition and as a result can be transmitted to puppies through the bitch's milk.

Question 30

Transplacental

Answer 30

the exchange of nutrients, waste products, drugs, infectious organisms, or other substances between the mother and the fetus.

Question 31

Tissue cyst

Answer 31

In the human host, the parasites form tissue cysts, most commonly in skeletal muscle, myocardium, brain, and eyes; these cysts may remain throughout the life of the host.

Question 32

Parthenogenic

Answer 32

a natural form of asexual reproduction in which growth and development of embryos occur in a gamete without combining with another gamete.

Question 33

Homogonic

Answer 33

being or characterized by a course of development in which one generation of parasites immediately succeeds another.

Question 34

Heterogonic

Answer 34

being or characterized by a course of development in which a generation of parasites is succeeded by a free-living generation.

Question 35

Hyperinfection

Answer 35

repeated reinfection with larvae produced by parasitic worms already in the body due to the ability of various parasites to complete the life cycle within a single host compare autoinfection.

Question 36

Hexacanth embryo

Answer 36

the embryo of tapeworms of the subclass Cestoda, such as Taenia saginata, characterized by three pairs of hooks used for penetration through the gut of an intermediate host.

Question 37

Metacestode

Answer 37

the larval stage of a tapeworm, found in an intermediate host.

Question 38

Proglottids

Answer 38

each segment in the strobila of a tapeworm, containing a complete sexually mature reproductive system.

Question 39

Species specificity

Answer 39

the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species

Question 40

Rostellum

Answer 40

a small beaklike process, such as the hooked projection from the top of the head in tapeworms or the outgrowth from the stigma of an orchid.

Question 41

Cysticercoid

Answer 41

the larval stage of certain tapeworms

Question 41

Cysticercoid

Answer 41

the larval stage of certain tapeworms

Question 42

Cysticercus

Answer 42

a small, bladder-like cyst

Question 43

Cysticercus

Answer 43

a small, bladder-like cyst

Question 44

Wolbachia sp.

Answer 44

harbored in worms

Question 45

sporocyst

Answer 45

In adult ticks, sporocysts develop within oocysts and dog becomes infected after eating a tick

Question 46

sporozoite

Answer 46

constitutes the first form of the malaria parasite entering the human body ## Footnote upon ingestion of sporocysts, sporozoites can either enter GI cells or disseminate to other tissues

Question 47

Diplomonad

Answer 47

a group of flagellates, most of which are parasitic.

Question 48

Immunodiagnostics

Answer 48

tests to detect antibodies and parasite antigens

Question 49

Baermann

Answer 49

sedimentation for heavier eggs

Question 50

McMaster’s

Answer 50

fecal floatation, dilution technique

Question 51

Knott’s test

Answer 51

used to detect and identify microfilariae of filarid nematodes in blood. ## Footnote heartworm

Question 52

Merogony/schizogony

Answer 52

A form of asexual reproduction whereby a parasitic protozoan replicates its own nucleus inside its host's cell and then induces cell segmentation; schizogony

Question 53

Gamogony/gametogony

Question 53

Gamogony/gametogony

Question 54

sporogony

Answer 54

the asexual process of spore formation in parasitic sporozoans.

Question 55

# Specific features of Nematodes

Answer 55

* Buccal cavity: is modified in the form of a hollow spear, adapted to penetrate and withdraw the contents of host cells. * Bursa: a lobular modification of the male posterior end in some groups of nematodes which is highly elaborated in strongylid nematodes * Dioecious: having individuals of separate sexes.

Question 56

# Specific qualities of: Trematodes

Answer 56

* Monoecious: having both the male and female reproductive organs in the same individual * Dioecious: having the male and female reproductive organs in separate individuals. * Acetabula: sucker

Question 57

Cestodes

Answer 57

Proglottids: segments with reproductive parts strobila: a more developed form of a cysticercus scolex: holdfast organs rostellum: beak like head

Question 58

Protozoans

Answer 58

* Flagellates * Kinetoplasts: flagellated protozoans, which are unicellular eukaryotic organisms. * Cyst * Trophozoite: animal that feeds