unit 8 vocab

Question 1

ameba (pl. amebae)

Answer 1

a single-celled eukaryotic organism lacking a definite shape and moving by means
of pseudopodia; also spelled amoeba (pl. amoebae)

Question 2

arthropod

Answer 2

a member of the phylum Arthropoda, which includes crustaceans, insects, and arachnids

Question 3

atrial

Answer 3

of or relating to a body cavity

Question 4

cestode

Answer 4

/ tapeworm; member of the class Cestoda

Question 5

commensal

Answer 5

/ an organism that lives with, on, or in another organism, without injury to either

Question 6

congenital

Answer 6

/ acquired during fetal development, and present at the time of birth, but not inherited

Question 7

cyst

Answer 7

the dormant stage of an organism surrounded by a resistant covering; the nonmotile, nonfeeding stage of
a protozoan parasite; a closed sac-like structure within a tissue

Question 8

definitive host

Answer 8

the host in which the sexual or adult form of the parasite is found

Question 9

ectoparasite

Answer 9

/ a parasite that lives on the outer surface of a host

Question 10

endemic

Answer 10

/ recurring in a specific location or population

Question 11

endoparasite /

Answer 11

a parasite that lives within the host

Question 12

helminth

Answer 12

a worm, especially a parasitic worm; in parasitology, the group comprising the roundworms
and flatworms

Question 13

host

Answer 13

the organism from which a parasite obtains nutrients and in which some or part of the parasite’s life cycle
is completed

Question 14

immunocompromised

Answer 14

having reduced ability or inability to produce a normal immune response

Question 15

intermediate host

Answer 15

the host in which the asexual, immature, or larval form of the parasite is found

Question 16

larva

Answer 16

immature stage of an invertebrate

Question 17

mechanical vector

Answer 17

a vector (usually an arthropod) that is not essential to a parasite’s life cycle but that can transfer
an infective parasite to a noninfected host

Question 18

nematode

Answer 18

roundworm; any unsegmented worm of the class Nematoda

Question 19

opportunistic parasite

Answer 19

an organism that causes disease only in immunocompromised hosts

Question 20

parasite

Answer 20

/ an organism that lives in or on another species and at the expense of that species

Question 21

pathogenic /

Answer 21

capable of causing damage or injury to the host

Question 22

primary amebic encephalitis (PAM) /

Answer 22

rare and usually fatal central nervous system infection caused by Naegleria
fowleri ameba

Question 23

proglottid (pl. proglottids)

Answer 23

the tapeworm body segment that contains the male and female reproductive organs

Question 24

protozoa

Answer 24

unicellular eukaryotic organisms, both free-living and parasitic

Question 25

reservoir host

Answer 25

a host, other than the usual host, in which the parasite lives and is infectious

Question 26

sporozoite

Answer 26

the banana-shaped motile infective stage of certain apicomplexan protozoa such as Toxoplasma, Cryptosporidium, and Plasmodium; in Plasmodium, the stage present in mosquito salivary glands that is introduced into blood by mosquito bite

Question 27

trematode

Answer 27

/ fluke; any parasitic flatworm of the class Trematoda

Question 28

trophozoite

Answer 28

the motile feeding stage of protozoan parasites

Question 29

trypomastigote

Answer 29

the characteristic developmental stage of trypanosomes, which has a leaf-like form, an undulating membrane, and usually a free flagellum

Question 30

vector

Answer 30

an agent that transports a pathogen from an infected host to a noninfected host

Question 31

ameba (pl. amebae)

Answer 31

a single-celled eukaryotic organism lacking a definite shape and moving by means of pseudopodia; also spelled amoeba (pl. amoebae

Question 32

bradyzoite

Answer 32

a slowly multiplying form of coccidian parasite found within tissue cysts and typical of chronic infection with Toxoplasma gondii

Question 33

formalin

Answer 33

/ a 37% solution of formaldehyde used for fixing and preserving biologic specimens

Question 34

granulomatous amebic encephalitis (GAE)

Answer 34

rare and usually fatal brain infection caused by Acanthamoeba species and usually occurring only in immunocompromised individuals

Question 35

micrometer

Answer 35

a ruled device for measuring small objects

Question 36

ocular micrometer

Answer 36

a clear glass disk that fits in the microscope eyepiece, is etched with an arbitrary scale, and is used to measure objects viewed with the microscope; also called ocular reticle

Question 37

oocyst

Answer 37

the infectious, thick-walled, resistant stage of coccidian parasites, such as Toxoplasma and Cryptosporidium, which is found in the definitive host of the parasite

Question 38

pinworm

Answer 38

Enterobius vermicularis, a small parasitic nematode; seatworm

Question 39

primary amebic encephalitis (PAM)

Answer 39

rare and usually fatal central nervous system infection caused by Naegleria fowleri amebae

Question 40

proglottid

Answer 40

the tapeworm body segment that contains the male and female reproductive organs

Question 41

pseudopod/pseudopodium (pl. pseudopods/pseudopodia)

Answer 41

a temporary extension of cytoplasm of certain single-celled organisms such as ameba, that is used for movement and feeding

Question 42

PVA

Answer 42

polyvinyl alcohol, a preservative used for fecal specimens

Question 43

tachyzoite

Answer 43

a rapidly multiplying stage in the development of the tissue phase of certain coccidians, as in acute Toxoplasma gondii infections

Question 44

tissue cyst

Answer 44

/ intracellular cysts located within host tissues and containing organisms in a state of reduced metabolism that can survive and remain infectious for years

Question 45

trophozoite

Answer 45

he motile feeding stage of protozoan parasites

Question 46

trichrome stain

Answer 46

a stain commonly used to identify parasites in fecal smears

Question 47

Anopheles

Answer 47

/ the genus of mosquito that is the definitive host for the human malaria parasites (genus Plasmodium) and that is capable of transmitting the organism to humans

Question 48

babesiosis

Answer 48

/ an infection spread by tick bite and caused by protozoan parasites of the genus Babesia

Question 49

Giemsa stain

Answer 49

a polychromatic stain used for staining blood cells and blood parasites

Question 50

malaria

Answer 50

in humans, a disease caused by infection with protozoan parasites of the genus Plasmodium

Question 51

microfilaria (pl. microfilariae)

Answer 51

immature form of a filarial worm

Question 52

parasitemia

Answer 52

/ parasites in the blood

Question 53

paroxysm(s)

Answer 53

the cycle(s) of chills and fever associated with malaria that occur 36 to 72 hours apart, depending on the Plasmodium species

Question 54

Plasmodium

Answer 54

the protozoan genus that includes the organisms causing human malaria