Parasitology Finals

A. Hepatocytes

Which of the following parts of the body does the infective stage of *Plasmodium* spp. to man travel to once it enters the body?



A. Hepatocytes                        

B. Erythrocytes                        

C. Macrophages

D. Pancreatic cells

E. Neurons

D. Stiff, Rotary motility

A 6-year old patient was rushed to the Emergency Room due to watery diarrhea accompanied by flatulence that smells like rotten eggs. The ER doctor requested for Fecalysis to test for the presence of parasites. The RMT noticed that the microorganism looked like an old man with glasses. Which of the following motility patterns characterize this parasite’s movement?



A. Corkscrew motility                

B. Ping pong motility                

C. Falling leaf motility

D. Stiff, Rotary motility

E. Tumbling motility

E. *Giardia intestinalis*

The main symptom of an infection with *Enterobius vermicularis* show similar main symptom of what protozoa?



A. *Chilomastix mesnilli*              

B. *Dientamoeba fragilis*             

C. *Entamoeba histolytica*

D. *Iodamoeba butschlii*

E. *Giardia intestinalis*

D. Chronic Form

Which form of *Balantidium coli* is associated with constipation and abdominal pain?

A. Asymptomatic carriers

B. Fulminant Balantidiasis

C. Balantidial dysentery

D. Chronic Form

E. Incubation Period

B. *Plasmodium malariae*

This parasite’s macrogametocyte has an eccentric chromatin mass but a delicate light-brown pigment may be visible throughout the cell.



A. *Plasmodium falciparum*         

B. *Plasmodium malariae*            

C. *Plasmodium knowlesi*

D. *Plasmodium vivax*

E. *Plasmodium ovale*

E. Concentration techniques

This is the test for coccidians that is considered as a basic method for their microscopic detection.



A. Safranin and Microwave heating

B. Acid-Fast staining technique

C. Fluorescence microscopy

D. Polymerase chain reaction

E. Concentration techniques

D. *Plasmodium vivax*

This parasite’s cytoplasm is rounded with compact trophozoites, and they are occasionally slightly amoeboid, with growing trophozoites having large chromatin masses.



A. *Plasmodium falciparum*         

B. *Plasmodium malariae*            

C. *Plasmodium knowlesi*

D. *Plasmodium vivax*

E. *Plasmodium ovale*

B. I, II, III, IV

All are possible testing methods for *Cystoisospora belli*, except?

            I. Duodenal Aspirate Examination

            II. Peripheral Blood Smear

            III. Zinc Sulfate Concentration Technique

            IV. Formalin-Ether/Ethyl Acetate Concentration

            V. Auramine-Rhodamine Staining



A. I, II, III, IV, V                         

B. I, II, III, IV                             

C. II, III, IV, V

D. I, III, IV, V

E. I, II, III, V

D. I, III, IV, V

True regarding *Sarcocystis* species.



            I. Parasite undergoes sexual reproduction in definitive host’s intestines.

            II. In its second life cycle, the carnivores and omnivores pass the infectious stages in their feces

            III. Active bradyzoites enter the intestinal cells of the host and form gamonts

            IV. Laboratory diagnosis includes an elevated Erythrocyte Sedimentation Rate and elevated Creatine Kinase levels

            V. Solutions for flotation techniques are based on high-density solutions.



A. I, II, III, IV, V                         

B. I, II, III, IV                             

C. II, III, IV, V                           

D. I, III, IV, V

E. I, II, III, V

AB. I, II, IV, V

D. *Plasmodium vivax*

The erythrocytes that this species infect becomes enlarged, where the erythrocyte becomes 1-2x bigger than the normal erythrocyte diameter.



A. *Plasmodium falciparum*         

B. *Plasmodium malariae*            

C. *Plasmodium knowlesi*

D. *Plasmodium vivax*

E. *Plasmodium ovale*

A. *Entamoeba coli*

Amoeba with a characteristic cross-eyed cyst, a blot-like karyosome, and a comma-shaped chromatid.



A. *Entamoeba coli*                    

B. *Endolimax nana*                    

C. *Naegleria fowleri*

D. *Acanthamoeba* spp.

E. *Iodamoeba butschlii*

A. I, II, III, IV, V

True regarding the *Naegleria fowleri*.



            I. Free-living freshwater and soil Amoebaflagellate

            II. Enters the body through the nose, and travels along the olfactory nerves.

            III. Can grow in non-nutrient agar in conjunction with coliform growth

            IV. Isolated from bottled mineral waters in Mexico

            V. Causative agent of Primary Amebic Meningoencephalitis



A. I, II, III, IV, V                         

B. I, II, III, IV                             

C. II, III, IV, V                           

D. I, III, IV, V

E. I, II, III, V

AB. I, II, IV, V

C. Babesiosis

Refer to the picture below. This is seen during cases of what disease?

A. Malaria

B. Cystoisosporiosis

C. Babesiosis

D. Cryptococcosis

E. Cryptosporidiosis

C. *Entamoeba polecki*

Considered as a commensal in humans and it primarily infects monkeys.



A. *Entamoeba gingivalis*            

B. *Entamoeba dispar*                

C. *Entamoeba polecki*

D. *Iodamoeba butschlii*

E. *Endolimax nana*

C. II, IV

Not a characteristic of *Entamoeba coli*.



            I. Finger-like pseudopodia

            II. Sluggish, non-progressive movement

            III. Clean-looking inclusions

            IV. Can contain up to 8 nuclei

            V. Witch-broom stick appearance of chromatoidal bars

            VI. Eccentric karysome in the nucleus



A. I, II               

B. I, III              

C. II, IV            

D. II, V

E. IV, VI             

AB. V, VI

D. Metronidazole

For invasive amoebiasis, what medication can be used for treatment?

A. Dioxanide Furoate

B. Tinidazole

C. Paromomycin

D. Metronidazole

E. Iodoquinol

A. Plasmodium falciparum

This parasite’s merozoites form a “rosette” forming schizont inside RBCs.

A. Plasmodium falciparum

B. Plasmodium malariae

D. Plasmodium vivax

E. Plasmodium ovale

B. Culture of infected material

Of the following laboratory diagnostic methods, which is the most commonly used for the recovery of members of the L. braziliensis complex?

A. Schizodeme analysis

B. Culture of infected material

C. Identifying amastigotes in infected material

D. Zymodeme analysis

A. Visceral leishmaniasis

A common name for disease caused by L. donovani is:

A. Visceral leishmaniasis

B. Kala-azar

C. Dum dum fever

D. All of the choices

B. Phlebotomus sandfly

The vector responsible for the transmission of L. donovani is:

A. Lutzomyia sandfly

B. Phlebotomus sandfly

C. Psychodopygus sandfly

D. None of the choices

C. Senescent RBCs

P. vivax characteristically invades:

A. Immature RBCs

B. All RBCs

C. Senescent RBCs

D. Lymphocytes

C. Sporozoites

The infective stage of Plasmodium is

A. Merozoites

B. Oocysts

C. Sporozoites

D. Gametocyte

D. Chagas' disease

American trypanosomiasis is commonly referred to as:

A. Cruzon's syndrome

B. Chiclero ulcer

C. Bay sore

D. Chagas' disease

C. Trypomastigote

The diagnostic stage for Trypanosoma spp. is the:

A. Amastigote

B. Epimastigote

C. Trypomastigote

D. Promastigote

A. Trypanosoma brucei gambiense

Which of the following organisms causes the less aggressive form of sleeping sickness?

A. Trypanosoma brucei gambiense

B. Trypanosoma cruzi

C. Trypanosoma brucei rhodesiense

D. Trypanosoma rangeli

B. Amastigote

This is the only hemoflagellate morphologic form that does not have an external flagellum.

A. Trypomastigote

B. Amastigote

C. Promastigote

D. Epimastigote

D. Macrogametocyte

Which morphologic form is not typically seen in infections of P. malariae?

A. Mature schizont

B. Ring form

C. Immature schizont

D. Macrogametocyte

B. Single or double sporocysts

In addition to oocysts, these Sarcocystis morphologic forms may be seen in human samples:

A. Packets of eggs

B. Single or double sporocysts

C. Clusters of cysts

D. Groups of sporoblasts

D. Sterilize equipment using 5% to 10% household ammonia.

All the following are recommended to prevent and control an outbreak of Cryptosporidium except:

A. Proper treatment of water supplies

B. Sterilize equipment using high heat.

C. Sterilize equipment using full-strength bleach

D. Sterilize equipment using 5% to 10% household ammonia.

A. Saline wet prep

Which is the best screening method for the identification of Blastocystis hominis?

A. Saline wet prep

B. Modified acid-fast stain

C. Iodine wet prep

D. Iron hematoxylin stain

A. Proper water treatment

The most important Cyclospora prevention step that can be taken is:

A. Proper water treatment

B. Wearing shoes when walking in sandy soil

C. Insecticide treatment of mosquito breeding areas

D. Thoroughly cooking beef and pork.

B. Electron microscopy

Of the following, which laboratory technique is required for species identification of Microsporidia?

A. Giemsa-stained biopsy material

B. Electron microscopy

C. Fecal concentration

D. PAS stain

B. Extruding polar filaments

How do Microsporidia spores differ from other protozoan spores?

A. Double outer wall

B. Extruding polar filaments

C. Cilia

D. Pseudopods

A. Histologic stain

What is the preferred method of diagnosis for Pneumocystis jiroveci?

A. Histologic stain

B. Giemsa stain

C. Iron hematoxylin stain

D. Iodine wet prep

A. Accidental ingestion of rodent feces

Human infection of Toxoplasma is initiated in all the following ways except:

A. Accidental ingestion of rodent feces

B. Ingestion of contaminated undercooked meat from cattle, pigs, or sheep

C. Transplacental infection

D. Transfusion of contaminated blood

B. Tachyzoites

All the following are morphologic forms in the life cycle of Toxoplasma gondii except:

A. Oocysts

B. Tachyzoites

C. Bradyzoites

D. Sporozoites

A. Naegleria

The clinical symptoms associated with Cyclospora infections in children are similar to those seen in cases of infection by which of the following?

A. Naegleria

B. Cryptosporidium

C. Leishmania

D. Balantidium

A. P. falciparum

Patient diagnosed to have malaria; smear shows all stages of schizonts 14-20 merozoites, yellowish-brown pigment. The type of malaria is:

A. P. falciparum

B. P. ovale

C. P. vivax

D. P. malariae

E. P. knowlesi

A. P. falciparum

Which type of malaria is associated with nephrotic syndrome and renal failure?

A. P. falciparum

B. P. vivax

C. P. malariae

D. P. ovale

E. P. knowlesi

B. Due to adherence to the capillary endothelium, they are note seen in peripheral blood

Why are schizont and late trophozoite stages of Plasmodium falciparum re not seen in peripheral blood smear?

A. They are sequestered in the spleen

B. Due to adherence to the capillary endothelium, they are note seen in peripheral blood

C. Due to antigen-antibody reaction and removal, antibody dependent cytotoxic killing

D. They are seen in mosquito blood

B. Babesia microti

Maltese cross is a characteristic feature of:

A. Cryptosporidium sp.

B. Babesia microti

C. Blastocytosis

D. Toxoplasma sp.

E. Plasmodium ovale.

B. Schüffner's dots

Which morphologic characteristic may help in distinguishing P. vivax from P. falciparum?

A. Hemozoin

B. Schüffner's dots

C. 72-hour paroxysm

D. None of the above

D. Trypomastigote

It measures 12 to 35 µm long by 2 to 4 µm wide; assumes the shape of the letters C, S or U and has posteriorly located kinetoplast.

A. Amastigote

B. Promastigote

C. Epimastigote

D. Trypomastigote

C. Epimastigote

Approximately 9 to 15 µm in length; body is slightly wider than that of the promastigote and kinetoplast is located anterior to the nucleus.

A. Amastigote

B. Promastigote

C. Epimastigote

D. Trypomastigote

B. Kissing bug

. The intermediate host of Trypanosoma cruzi:

A. Sandfly

B. Kissing bug

C. Mosquito

D. Arthropods

C. Both A and B are correct

With the hemoflagellate _______ there are far more asymptomatic infections than clinical cases in humans.

A. Trypanosoma spp.

B. Leishmania spp.

C. Both A and B are correct

D. None of the above

D. Trypomastigote

Once the cell Trypanosoma cruzi amastigotes are infected dies and lyses, the amastigotes are released, and some will transform into _______ in the blood.

A. Amastigote

B. Promastigote

C. Epimastigote

D. Trypomastigote

B. Promastigote

Inside the sand fly midgut, Leishmania amastigotes transform into _______.

A. Amastigote

B. Promastigote

C. Epimastigote

D. Trypomastigote

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
8-36 merozoites in clusters/rosette arrangement

C

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Amoeboid trophozoite

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Crescentic gametocyte

B

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Round, compact trophozoite

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Involves in multiple infections

D

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Trophozoite is similar with P. vivax but smaller

C

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
12-24 merozoites arranged irregularly

B

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
6-12 merozoites arranged in irregular clusters

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
8-14 merozoites with rosette arrangement

D

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Ziemann’s dots (rarely present)

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Maurer’s dots (sometimes present)

A

**MATCHING TYPE. A. P. falciparum B. P. malariae C. P. vivax D. P. ovale E. None of the given options**

\
Accole: crescent-shaped mass at outer edge of RBC

B. Erythrocytic stage

Multiplication and differentiation of sporozoites into merozoites occurs in:

A. Exoerythrocytic stage

B. Erythrocytic stage

C. Both A and B

B. Sharing of IV needles

All of the following are possible mode of transmission of malaria, except:

A. Mosquito bite

B. Sharing of IV needles

C. Transplacental

D. Blood transfusion

E. None of the above

B. P. malariae

Symptoms recur every 4th day:

A. P. falciparum

B. P. malariae

C. P. vivax

D. P. ovale E

. None of the given options

E. All of the above

Dark colored urine is due to:

A. Liver damage

B. Kidney damage

C. Cardiac failure

D. Respiratory distress

E. All of the above

C. Both statements are true

Malarial thick blood smears are used for screening purposes. Thin smears are used for differentiation of Plasmodium spp.

A. 1st statement is true; 2nd statement is false

B. 1st statement is false; 2nd statement is true

C. Both statements are true

D. Both statements are false

B

**SEQUENCING. Which comes first? A. 1st B. 2nd C. 3rd D. 4th E. 5th**

\
Bloodstream trypomastigotes are ingested

D

**SEQUENCING. Which comes first? A. 1st B. 2nd C. 3rd D. 4th E. 5th**

\
Epimastigotes multiply in salivary gland

E

**SEQUENCING. Which comes first? A. 1st B. 2nd C. 3rd D. 4th E. 5th**

\
Tsetse fly injects trypomastigotes

C

**SEQUENCING. Which comes first? A. 1st B. 2nd C. 3rd D. 4th E. 5th**

\
Production of procyclic trypomastigotes in vector’s midgut

A

**SEQUENCING. Which comes first? A. 1st B. 2nd C. 3rd D. 4th E. 5th**

\
Trypomastigotes multiply by binary fission in body fluids i.e. blood, lymph, spinal fluid

A. True

The presence of IgM in serum is not considered as diagnostic for the detection of trypomastigotes.

A. True

B. False

D. Both statements are false

T. brucei gambiense is more virulent than T. brucei rhodesiense. T. brucei gambiense has shorter incubation period.

A. 1st statement is true; 2nd statement is false

B. 1st statement is false; 2nd statement is true

C. Both statements are true

D. Both statements are false

C. Both statements are true

Trypanosoma spp. and Leishmania spp. are both hemoflagellates. They are similar in their diagnostic stages.

A. 1st statement is true; 2nd statement is false

B. 1st statement is false; 2nd statement is true

C. Both statements are true

D. Both statements are false

E. None of the above

All of the following characterize the chronic phase of Chagas’ disease, except:

A. Hepatosplenomegaly

B. Lymphadenopathy

C. Myocarditis

D. Nodule near the bite site

E. None of the above

B. 1st statement is false; 2nd statement is true

Protozoans are microscopic multicellular eukaryotes that have complex internal structures. They have structures for propulsion or movement.

A. 1st statement is true; 2nd statement is false

B. 1st statement is false; 2nd statement is true

C. Both statements are true

D. Both statements are false

C. Both A and B are correct

Possible coinfection with HIV patients.

A. Leishmania spp.

B. Trypanosoma spp.

C. Both A and B are correct

D. None of the above

B. Promastigote

In the life cycle of Leishmania spp., _______________ that reach the puncture wound are phagocytized by macrophages and other types of mononuclear phagocytic cells.

A. Amastigote

B. Promastigote

C. Epimastigote

D. Trypomastigote

C. Diffuse Mucocutaneous

Also known as anergic leishmaniasis.

A. Cutaneous

B. Mucocutaneous

C. Diffuse Mucocutaneous

D. Visceral

E. All of the above

B. False

Montenegro test is a definitive test for Leishmaniasis.

A. True

B. False

B. Locomotion

Undulating membrane is a structure for:

A. Attachment

B. Locomotion

C. Reproduction

D. Growth

E. All of the above

B. 3-10 months

The meningoencephalitic phase of African Trypanosomiasis occurs _____ months after initial infections.

A. 2-10 months

B. 3-10 months

C. 5-10 months

D. 10-12 months

B. False

For immunocompromised host, the presence of elevated IgM levels in serum rules out trypanosomiasis.

A. True

B. False

B. False

Amebas transform from trophozoites to cysts on entry into an unsuspecting human.

A. True

B. False

B. Endolimax nana

Amoeba with a characteristic cross-eyed cyst, a blot-like karyosome, and a comma-shaped chromatid.

A. Entamoeba coli

B. Endolimax nana

C. Naegleria fowleri

D. Acanthamoeba spp.

E. Iodamoeba butschlii

C. Entamoeba polecki

Considered as a commensal in humans and it primarily infects monkeys.

A. Entamoeba gingivalis

D. Iodamoeba butschlii

B. Entamoeba dispar

E. Endolimax nana

C. Entamoeba polecki

This shows a bouquet-like pattern when the glycogen is stained with iodine.

A. Entamoeba coli

D. Acanthamoeba spp.

B. Endolimax nana

E. Iodamoeba butschlii

C. Naegleria fowler

A. Slaughterhouse workers dealing with pigs

Which occupation has the most susceptibility to Balantidium coli infections?

A. Slaughterhouse workers dealing with pigs

B. Veterinarians working with cats

C. Laboratory Technologist focusing on Fecalysis

D. Public Health worker assigned in West Africa

E. Restauranteur working in Palawan, Philippines

B. False

The conversion of trophozoites to cysts, a process known as excystation , occurs in the intestine when the environment becomes unacceptable for continued trophozoite multiplication.

A. True

B. False

B. Cysts

Formed stool specimens are more likely to contain which of the following?

A. Trophozoites

B. Cysts

A. Single nucleus with a small karyosome

Which of the following structures is (are) typical in trophozoites of E. histolytica?

A. Single nucleus with a small karyosome

B. Unevenly distributed peripheral chromatin

C. Chromatoid bars

D. Glycogen mass

B. Cysts contain at least four nuclei.

Which of the following statements is not true about the cysts of E. polecki?

A. Cysts vary in shape from spherical to oval.

B. Cysts contain at least four nuclei.

C. The typical cyst nucleus resembles that of E. histolytica.

D. A diffuse glycogen mass may be present in the cytoplasm of cysts.

B. The infective trophozoites are ingested in contaminated food or drink.

Transmission of I. bütschlii occurs when:

A. The infective cysts are ingested in contaminated food or drink.

B. The infective trophozoites are ingested in contaminated food or drink.

C. Examining stool specimens from infected individuals

D. An infected mosquito vector bites an unsuspecting human.

D. E. gingivalis is the only ameba that may ingest white blood cells.

Which of the following is a unique characteristic of E. gingivalis?

A. The trophozoites exhibit active motility via their pseudopods.

B.There is no known cyst form of this parasite

C. The trophozoite has a single nucleus with characteristics that resemble those of E. histolytica.

D. E. gingivalis is the only ameba that may ingest white blood cells.

D. Using homemade nonsterile saline solutions

To prevent infection with Acanthamoeba species, contact lens wearers should avoid which of the following?

A. Strenuous exercise

B. Foods with high carbohydrate content

C. Wearing clothing made of cotton

D. Using homemade nonsterile saline solutions

C. Trophozoites are resistant to the environment outside the host.

Which of the following statements is not true about amebic trophozoites?

A. Trophozoites are delicate and motile.

B. Trophozoites are easily destroyed by gastric juices.

C. Trophozoites are resistant to the environment outside the host.

D. Replication occurs in the trophozoite stage.

A. Macronucleus

Which structure is always visible in the stained cyst and trophozoite of Balantidium coli?

A. Macronucleus

B. Micronucleus

C. Cilia

D. Ingested bacteria

B. Decreased microscope light level

All the following are highly recommended when processing samples for the identification of Isospora belli to ensure identification except:

A. Iodine wet prep

B. Decreased microscope light level

C. Modified acid-fast stain

D. Saline wet prep

D. Mature oocysts

Which stage of reproduction is considered capable of initiating another infection of Isospora belli?

A. Sporozoites

B. Immature oocysts

C. Merozoites

D. Mature oocysts

C. contractile vacuoles

The osmoregulatory organelles of Balantidium coli is the

A. cytostome

B. cytopyge

C. contractile vacuoles

D. peristome

E. None of the choices

All of the following protozoan parasite can be cultured in the laboratory except for:

A. Entamoeba histolytica

B. Giardia lamblia

C. Balantidium coli

D. Acanthamoeba spp.

E. None of the choices