Unit 11.1 - 11.2B

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?