25
___% of all deaths worldwide are the result of parasites or complications from parasite infection.
safe water supply, sewage treatment
The two main reasons why parasite infection is uncommon in the US are:
fecal-oral
The most common route of transmission for parasites is:
tropical developing countries
Most parasitic infections occur in:
foreign travel, immigration
Incidence of parasitic infection in the US is on the rise mostly because of increasing:
fatal
As parasites have evolved alongside humans, they have become less:
compete for nutrients
Internal parasites can damage the lining of the GI tract, and:
secondary bacterial infection
Many complications from parasitic infections are actually the result of:
asymptomatic
Parasites can live in a host for a long time without causing symptoms, said to be:
eosinophilia
_______ is present in 15-50% of patients with parasitic infection.
nutrition
Since ______ affects the immune system, in areas where healthiful food is not available parasitic infections are more common.
survive frozen in the soil
Parasites are uncommon in colder areas because cysts often cannot:
symbiosis
The relationship of two organisms living together is:
parasitism
A relationship in which one organism is physically dependent on another is:
mutualism
A relationship in which both organisms are physically dependent on each other is:
commensalism
A relationship in which one organism benefits but no damage is done to either organism is:
stool
Intestinal parasites are recovered in this specimen:
3, 10
For optimum recovery of organisms, _____ O&P specimens should be collected over _____ days.
formalin, PVA
In a two vial O&P collection set, one vial contains _____ and the other contains _____.
direct wet prep
This is performed on fresh stool and looks only for trophozoites:
formalin ethyl-acetate technique
This is the most common centrifugation procedure is:
lugol's or d'antoni iodine
A wet mount made from preserved stool is stained with:
trichrome, iron hematoxylin
A permanent slide made from preserved stool is stained with:
acid fast stain
Cryptosporidium, Clyclospora, and Isospora all stain positive with:
serpentine
Permanent smears should be examined on oil immersion using a(n) ______ pattern.
immunologic testing
Sometimes ______ can be substituted for O&P, especially if a specific organism is suspected.
cyst
This is the _____ form of an amoeba.
nucleus
A:
fibril
B:
cytoplasm
C:
chromatoidal bar
D:
karyosome
E:
trophozoite
This is the _____ form of an amoeba.
inclusion
A:
nucleus
This structure is present in all amoebas and how many are present can help in identification:
chromatin
Condensed DNA or RNA is:
peripheral chromatin
Chromatin that lines the inside of the nuclear membrane is:
even
The peripheral chromatin of this nucleus is:
rough
The peripheral chromatin of this nucleus is:
karyosome
A small mass of chromatin located within the nucleus is a(n):
central
This karyosome is:
eccentric
This karyosome is:
fibrils
Lines of chromatin connecting the karyosome to the peripheral chromatin are:
chromatoidal bar
Condensed RNA found in the cytoplasm is:
smooth
The ends of this chromatoidal bar are:
splintered
The ends of this chromatoidal bar are:
cytoplasm
Everything between the cell membrane and the nucleus is:
fine, granular, coarse
The terms used to describe the cytoplasm of amoebas are:
rbcs, yeast, bacteria, glycogen
Inclusions within amoebas may contain:
cyst
This is the infectious stage of amoebas:
trophozoite
This is the invasive and replicative stage of amoebas:
excystation
The process by which a cyst morphs into a trophozoite is:
encystation
The process by which a trophozoite morphs into a cyst is:
sarcomastigophora
Amoebas belong to the phylum:
sarcodina
Amoebas belong to the subphylum:
pathogenic
E. histolytica is the only intestinal amoeba that is:
amoebic dysentery
10% of E. histolytica infections will progress to:
3rd
Amoebic dysentery is the ____ leading cause of death due to parasites.
weight loss, fatigue
Symptoms of amoebic dysentery include abdominal pain, diarrhea, ______, and _____.
liver
Amoebic dysentery may cause lesions on the:
contaminated food or water
E. histolytica cysts enter the body by consumption of:
enzymes lysing host cells
A lot of the tissue damage from E. histolytica infection is caused by:
bloody
Diarrhea in E. histolytica infection is often:
extra-intestinal
Lesions on the liver are a frequent cause of death in E. histolytica- this is termed ______ disease.
metronidazole
First line treatment for E. histolytica is:
round
E. histolytica cysts are _____ in shape.
1-4
E. histolytica cysts have ____ nuclei.
central
The karyosome of E. histolytica is:
even
The peripheral chromatin of E. histolytica is:
rounded
When present, the chromatoidal bars of E. histolytica have ______ ends.
progressive
The motility of E. histolytica trophozoites is:
rbc inclusions
This feature of E. histolytica trophozoites is diagnostic:
1
E. histolytica trophozoites have ____ nucleus/nuclei.
E. hartmanii
This amoeba is nearly indistinguishable from E. histolytica but is nonpathogenic:
size
The only difference between E. hartmanii and E. histolytica is:
micrometer
This tool is necessary to distinguish between E. hartmanii and E. histolytica:
1/2-2/3
E. hartmanii is on average ___-___ the size of E. histolytica.
nonpathogenic
E. coli is similar in appearance to E. histolytica but is:
4-32
E. coli cysts have _____ nuclei.
eccentric
The karyosomes of E. coli are:
rough
The peripheral chromatin of E. coli is:
splintered
When visible, the chromatoidal bars of E. coli cysts have _____ ends.
yeast, bacteria
The trophozoites stage of E. coli can have vacuoles that contain:
larger
E. coli is generally ______ than E. histolytica.
Endolimax nana
This is the smallest of the covered intestinal amoebas and is nonpathogenic:
1-4
E. nana cysts have ____ nuclei.
not present
The peripheral chromatin of E. nana is:
oval
E. nana cysts are _____ in shape.
blot-like
The karyosome of E. nana is:
rarely seen
The trophozoite stage of E. nana is:
iodamoeba butschlii
The cyst of this nonpathogenic intestinal amoeba has only one nucleus:
irregular
The karyosome of I. butschlii is:
glycogen vacuole
I. butschlii is characterized by its prominent:
sluggish
The trophozoite form of I. butschlii has _____ motility.
Naegleria fowleri
This is the only amoeba known to have three morphological forms:
central nervous system
Unlike the other amoebas which are intestinal protozoa, N. fowleri targets the:
primary amoebic meningoencephalitis
N. fowleri causes:
large
The karyosome of N. fowleri is:
not present
The peripheral chromatin of N. fowleri is:
slug like pseudopods
N. fowleri trophozoites are characterized by:
flagellate
N. fowleri has a(n) _____ form which exhibits a specific type of motility.
jerky
The flagellate form of N. fowleri has this type of motility:
flagellate
The ______ form of N. fowleri is the invasive form:
swimming
Humans encounter N. fowleri trophozoites when:
csf, nasal drainage
N. fowleri may be isolated from _____ or _____.
acanthamoeba
This genus consists of amoebas which are found free-living in warm water and enter the body through cuts in the skin or cornea:
amoebic encephalitis
Acanthamoeba spp cause:
blastocystis homins
This species is of unknown pathogenicity and is about the size of a yeast:
nonstaining vacuole
Blastocystis homins is identified by its:
flagella
This structure is used for movement and may be located on the anterior or posterior end of the organism:
undulating membrane
This structure is an extension of the cell membrane and helps movement:
costa
This structure connects the undulating membrane to the body of the parasite:
cytostome
This structure acts as a rudimentary mouth for flagellates:
axostyle
This structure is a rodlike support structure:
Giardia lamblia
This is the most prevalent parasite in the US and Canada:
4
Giardia cysts have up to ____ nuclei.
oval
Giardia cysts are ______ in shape.
2
Giardia cysts have ____ axostyle(s).
median bodies
Dark inclusions within the body of a flagellate are termed:
monkey face
Giardia trophozoites are said to have this appearance:
2
Giardia trophozoites have ___ nuclei.
median body
Giardia trophozoites have a single _____ perpendicular to their axostyle.
sucking disks
Giardia trophozoites have _______ that they use to adhere to the walls of the duodenum and the bile duct.
contaminated water
Giardia cysts are ingested in:
falling leaf
Giardia trophozoites exhibit characteristic ______ motility.
giardia lamblia
Which flagellate is this?
shed cysts
Patients infected with Giardia that are asymptomatic are still problematic because they:
self-limiting
Giardiasis usually causes mild gastrointestinal symptoms and is:
malabsorption syndrome
When Giardiasis causes severe diarrhea, weight loss, and fatigue it is termed:
visualization of organism in stool
The simplest way of diagnosing Giardiasis is:
immunofluorescence
Giardia can be identified using this type of stain:
enterotest
This test involves swallowing a capsule that collects Giardia:
metronidazole
The first line treatment for Giardiasis is:
sarcomastigophora
Flagellates belong to the phylum:
mastigophora
Flagellates belong to the subphylum:
trichomonas vaginalis
This flagellate causes a common sexually transmitted disease:
vagina, urethra
Trichomoniasis can effect the:
asymptomatic
Males infected with Trichomonas are usually:
jerky
When alive, Trichomonas vaginalis has this type of motility:
undulating membrane
Trichomonas spp have this distinctive feature:
1
Trichomonas spp have ____ axostyle(s).
trichomonas vaginalis
What parasite is this?
trichomonas hominis
This protozoan is very similar in appearance to T. vaginalis but is nonpathogenic:
undulating membrane is full length of cell
This is the feature that distinguishes T. hominis from T. vaginalis:
metronidazole
First line treatment for Trichomoniasis is:
chilomastix mesnili
This is a commensal flagellate that lives in the intestinal tract:
lemon
C. mesnili cysts have a characteristic _____ shape.
hyaline knob
A structure distinct to C. mesnili cysts is:
posterior end
C. mesnili trophozoites have a pointed:
spiral groove
This can sometimes be visualized on C. mesnili trophozoites:
dientamoeba fragilis
This flagellate has both flagellate and amoeba characteristics:
2
D. fragilis has ____ nuclei.
diarrhea, abdominal pain
D. fragilis is often asymptomatic but can cause:
ascaris, pinworm
D. fragilis is often found alongside these parasites:
ciliophora
Ciliates belong to the phylum:
pigs
______ are the natural reservoir of Balantidium coli.
balantidium coli
Symptoms of this ciliate resemble those of amoebic dysentery:
largest protozoan
Balantidium coli is the ______ that infects humans.
cilia
B. coli cysts and trophs are characterized by the presence of:
micro, macro
B. coli has two nuclei:
cell wall
B. coli cysts have a(n) _____ which may obscure the cilia.
nemathelminthes
Nematodes are in this phylum:
nematoda
Nematodes are in this class:
enterobius vermicularis
The most common helminth parasite in the US is:
pinworm
E. vermicularis is colloquially known as the:
rectal itching
E. vermicularis infection causes ______, along with restlessness and insomnia
ingestion of eggs
E. vermicularis infection begins with:
small intestine
E. vermicularis eggs hatch in the:
large intestine
E. vermicularis adults mate in the:
perianal
E. vermicularis females lay their eggs (shown) in this area:
retroinfection
When E. vermicularis eggs hatch and return to the small intestine of the host, this is termed:
mebendazole
The treatment for E. vermicularis is:
blocking uptake of glucose
Mebendazole kills nematodes by:
stool exam
E. vermicularis is the only helminth parasite for which _______ may be of little value.
cellophane tape method
The best way to recover and identify pinworms is:
thick colorless shell
E. vermicularis ova consist of a developing larva surrounded by a(n):
flattened side
E. vermicularis ova have this distinctive feature:
pointed
E. vermicularis worms have ______ tails.
alae
This structure shown on the anterior end of E. vermicularis worms is termed:
ascaris lumbricoides
The most common helminth parasite worldwide is:
roundworm
A. lumbricoides is colloquially known as the:
asymptomatic
Light to moderate A. lumbricoides infections are typically:
small intestine
Adult A. lumbricoides worms and maturing larva live in the:
intestinal blockage
Heavy infections with A. lumbricoides can cause:
wormball
A heavy infection with A. lumbricoides can produce this:
secondary bacterial infection
A common sequela of roundworm infection is:
mebendazole
First line treatment for nematodes is:
ingests mature ova
The A. lumbricoides life cycle begins when a human:
duodenum
A. lumbricoides eggs hatch in the:
liver, lungs
A. lumbricoides larva travel via the blood stream to the _____ and the _____ before returning to the gastrointestinal tract.
coughed up, swallowed
A. lumbricoides larva access the intestinal tract from the lungs by being _____ and _______.
chitin shell
Unfertilized A. lumbricoides eggs consist of a single celled embryo surrounded by a(n):
barrel
Fertilized A. lumbricoides eggs become ______ shaped.
corticated
The chitin shell of fertilized A. lumbricoides eggs is said to be:
roundworm
What organism will this egg hatch into:
roundworm
This is a mature adult:
lateral line
Roundworms can be distinguished by their size and the presence of a(n):
trichuris trichiura
This is the third most common helminth parasite in the US, and is mostly found in the southeastern region:
whipworm
T. trichiura is colloquially known as the:
warm, moist soil
T. trichiura eggs require 14 days in _______ to mature.
growth retardation
Symptoms of whipworm infection include chronic dysentery, anemia, and in children:
football
T. trichiura ova are ______ shaped.
hyaline plugs
T. trichiura ova have this characteristic feature:
whipworm
What worm will this egg hatch into?
whipworm
What worm is shown here?
hookworm
Necator americanus and Ancyclostoma duodenale are collectively known as the:
necator americanus
The scientific name for the New World Hookworm is:
ancyclostoma duodenale
The scientific name for the Old World Hookworm is:
southeast
Hookworms are prevalent in this area of the US:
anemia
The primary clinical manifestation of hookworm infection is:
0.25
One hookworm can consume ____ mL of blood per day.
soil
Hookworm eggs (shown) hatch in the:
rhabditiform
The ______ larva of a hookworm is the feeding form.
filariform
The _____ larva of a hookworm is the infectious form.
soles of feet
Filariform hookworm larvae enter the body through:
ground itch
The site where the hookworm larva enters is affected by this condition:
lungs
Filariform hookworm larvae travel through the bloodstream from the feet to the:
coughed up, swallowed
Hookworm larvae gain entrance to the intestinal tract by being _______ and _____.
mebendazole
Hookworm is treated with:
clear embryonic fluid
Hookworm eggs consist of a developing larva surrounded by ______ within a thick shell.
cells
Hookworm eggs usually have easily distinguishable:
strongyloides stercoralis
This organism is similar to a hookworm:
threadworm
S. stercoralis is also known as the:
rhabditiform larva
Only at this stage is S. stercoralis distinguishable from a hookworm:
skin, lungs
S. stercoralis causes disease of these organs:
buccal cavity
The _______ of S. stercoralis is much shorter than that of a hookworm.
genital primordium
S. stercoralis has a much more prominent ______ than hookworms.
hookworm
This is the rhabditiform larva of a(n):
threadworm
This is the rhabditiform larva of a(n):
tapeworms
Cestodes are colloquially known as:
hexacanth embryos
Cestode eggs contain:
hexacanth
This term refers to having 3 pairs of hooklets:
cysticercus
This term refers to the larval stage of tapeworms:
water
Cestode cysticerci are bladder-like cysts filled with:
cysticercosis
The presence of cysticerci outside of the intestinal tract is known as:
scolex
The head of a cestode worm is termed the:
rostellum
A structure at the very anterior end of the scolex is the:
attachment
The main purpose of the scolex is:
proglottid
Each individual segment of a cestode worm is a(n):
strobila
The ribbon-like chain of proglottids that makes up a cestode worm is known as the:
gravid
Proglottids which are fertilized and producing eggs are said to be:
tegument
The outer surface of a tapeworm is the:
absorb nutrients, excrete waste
The purposes of the tegument are:
Taenia saginata
This species is also known as the beef tapeworm:
Taenia solium
This species is also known as the pork tapeworm:
intermediate
Cows or pigs are the ______ hosts of Taenia spp tapeworms, which they acquire by consumption of the hexacanth embryos on the grass which they eat.
cysticerci
Within the muscles of pigs and cows, Taenia spp hexacanth embryos grow into:
definitive
Humans are the _____ hosts of Taenia spp tapeworms, which they acquire by consumption of undercooked beef or pork.
accidental intermediate, cysticercosis
If a human consumes a hexacanth embryo, they become a(n) _________ host and develop a condition called ______.
epilepsy
A common finding of cysticercosis in humans is:
beef
The ____ tapeworm is typically 25-50 feet long.
pork
The ____ tapeworm is typically 8-10 feet long.
T. solium, T. saginata
This ova could hatch into which species?
hexacanth hooklets
In this image, A represents:
radial striations
In this image, B represents:
adult worm
T. solium and T. saginata can only be differentiated in the _______ stage.
T. saginata
This tapeworm species has no rostellum:
T. solium
This tapeworm species has a rostellum:
saginata
Shown are gravid proglottids of the two Taenia species. Which species is A?
solium
Shown are gravid proglottids of the two Taenia species. Which species is B?
fish tapeworm
Diphyllobothrium latum is also known as the:
pernicious anemia
D. latum primarily causes:
fresh water
D. latum proglottids mature into ciliated eggs in:
coracidia
D. latum ciliated eggs are also known as:
copepods
D. latum coracidia are consumed by the 1st intermediate host:
fish
The 2nd intermediate host of D. latum, ____, acquires it by consuming copepods.
humans
The definitive host of D. latum, ______ acquires it by consuming undercooked fish.
feces
Within humans, D. latum reproduces and thus gravid proglottids return to the environment via:
operculum
In this image of a D. latum egg, A represents:
terminal knob
In this image of a D. latum egg, B represents:
rosette
This image shows the characteristic _____ shape of D. latum uterine structures.
sucking grooves
This image shows the characteristic ______ on the scolex of a D. latum worm.
fish tapeworm
This tapeworm is typically about 30 feet in length:
dog and cat tapeworm
Dipylidium caninum is also known as the:
fleas
The intermediate host of D. caninum is:
dogs, cats
The definitive hosts of D. caninum are:
accidental
Humans are a(n) _____ host of D. caninum, acquired by contact with infected dogs and cats.
gastrointestinal
Humans infected with D. caninum are typically asymptomatic at low worm loads, but at high worm loads may exhibit ______ symptoms.
5-30
D. caninum ova typically are contained in packets of ___-___ eggs.
rat and mouse tapeworm
Hymenolepis diminuta is also known as the:
accidental
Humans are a(n) ______ host of H. diminuta.
dwarf tapeworm
Hymenolepis nana is also known as the:
humans
H. nana only ever infects:
fecal-oral, autoreinfection
Humans may be infected with H. nana by one of these routes:
polar thickening
This is a primary distinguishing characteristic of H. diminuta ova:
filaments
This is a primary distinguishing characteristic of H. nana ova:
H. diminuta
This egg will hatch into which species of tapeworm?
H. nana
This egg will hatch into which species of tapeworm?