5BIOM009W Human Parasitology Example MCQ Questions PDF

5BIOM009W Human Parasitology Example MCQ Questions Specimen for Question 1 and 2 1. A rapid malaria diagnostic test was performed for a person presenting with symptoms of fever, every 48 hours, chills, and head and body aches, who had recently been travelling around different countries in sub...

5BIOM009W Human Parasitology Example MCQ Questions Specimen for Question 1 and 2 1. A rapid malaria diagnostic test was performed for a person presenting with symptoms of fever, every 48 hours, chills, and head and body aches, who had recently been travelling around different countries in sub-Saharan Africa. Which of the following sentences would be the most accurate interpretation of the result shown in the image? a. The RDT result is positive for P. falciparum only b. The RDT result is positive for P. falciparum +/- other Plasmodium species c. The RDT result is positive for P. vivax/P. ovale/P.malariae only d. The RDT result is invalid because there is no control band present e. The RDT result is negative 2. The OptiMAL-IT test used in Question 1 detects which Plasmodium antigen? a. Histidine-rich protein II (HRP-II) b. Parasite lactate dehydrogenase (pLDH) c. Aldolase d. Histodine-rich protein II (HPR-II) and Aldolase e. All of the above Specimen for Questions 3 and 4 3. The image is of a Giemsa-stained thin blood film (x1000 magnification) from the individual in Question 1. Which of the following is the correct parasite and life cycle stage seen in the blood film? a. Plasmodium vivax gametocyte b. Plasmodium falciparum trophozoite c. Plasmodium vivax trophozoite d. Plasmodium falciparum gametocyte e. Plasmodium malariae gametocyte 4. Which of the following sets of characteristics best fits the parasite stages shown in the images from Question 3 and helped you with your diagnosis? a. Infected erythrocytes with single or multiple ring stages, with thin delicate cytoplasm and small chromatin dots. Enlargement of infected cells. b. Infected erythrocytes with sausage-shaped gametocytes, thin delicate ring stages and Schüffner’s dots. Infected cells not enlarged. c. Infected erythrocytes with sausage-shaped gametocytes and ring-from trophozoites exhibiting Maurer’s clefts. d. Infected erythrocytes with amoeboid trophozoites and Schüffner’s dots, immature and mature schizonts, and rounded gametocytes. Enlargement of infected cells. e. Enlarged infected erythrocytes with schizonts and sausage-shaped gametocytes. 5. Which of the following statements about the diagnosis of the parasite from Questions 3 and 4 is not true a. Microscopy is the “gold standard” for malaria diagnosis b. Quantification may be done on both thick and thin blood smears c. Only life cycle stages associated with merozoite and gametocyte development can be seen in a blood film d. Giemsa is the preferred stain for malaria diagnosis e. Confirmation of infection by microscopy is not required following an RDT 8. The RFLP technique you employ uses a restriction enzyme on a PCR product that has been amplified. What do restriction enzymes do? a. Add nucleotides at specific points along a DNA molecule b. Cut a part of a protein c. Cut at specific nucleotides along a DNA molecule d. Join proteins to nucleotides e. None of the available answers 9. The image shows stages of Leishmania parasites in a Giemsa-stained tissue scraping (A) and from a laboratory culture (B). What forms of the Leishmania parasites can be seen in (A) and (B)? a. amastigotes and trypomastigotes b. amastigotes and promastigotes c. epimastigotes and promastigotes d. amastigotes and epimastigotes e. epimastigotes and trypomastigotes Specimen for Question 10. Which of the following is not true regarding the diagnosis of Leishmania infections? a. Serology can be useful in diagnosing visceral leishmaniasis but is of limited value in cutaneous leishmaniasis, since most patients do not develop a significant antibody response b. Leishmania amastigotes are indistinguishable from the amastigotes of Trypanosoma cruzi c. Isoenzyme analysis of Leishmania parasites isolated in culture using biphasic medium can be used to characterise the parasites to complex and sometimes species level but this can take several weeks  d. In the human host, both amastigote and promastigote stages can be seen upon microscopic examination of tissue specimens e. None of the available answers are false Specimen for Question 14 14. The image shows one of the sandfly vectors of the parasites from Questions 6- 10. Which of the following is the correct Family that this vector belongs to? a. Culicidae b. Glossinidae c. Triatominae d. Psychodidae e. Cratomyiidae Specimen for Question 15 15. The image shows Giemsa-stained parasite stages in a salivary gland smear from an infected adult female Anopheles mosquito (x1000 magnification). Which stage of the parasite from Questions 3 and 4 can be seen? a. Hypnozoites b. Sporozoites c. Oocysts d. Gametocytes  e. Schizonts Which of the following statements is not true about Anopheline mosquito species? a. The larvae of this type of mosquito rest parallel to water surfaces, with only a rudimentary breathing tube b. Mosquitos are dipterans (or, true flies) that belong to the family Culicidae c. When resting the proboscis and body of the adult mosquito is positioned at an angle to one another d. Only the adult female mosquito feeds on blood, males feed instead on nectar and other sugar sources e. All of the available answers Specimen for Question 19 4 3 2 1 19. Concentration techniques increase the sensitivity for identification of intestinal parasites in stool samples. The image above illustrates the principle of the formalin- ethyl acetate sedimentation concentration method showing the four layers following final centrifugation. Which of the following is the correct order of layers matching layers 1-4 labelled in the image from bottom to top of the tube? a. Sediment for egg counting, ethyl acetate, debris, formalin b. Formalin, sediment for egg counting, ethyl acetate, debris c. Ethyl acetate, sediment for egg counting, formalin, debris d. Sediment for egg counting, formalin, debris, ethyl acetate e. Debris, formalin, sediment for egg counting, ethyl acetate Specimen for Question 20 20. These images show schistosome eggs in liver tissue (x400 magnification, Haematoxylin and Eosin stain) from a patient with a history of travel to North Africa who was hospitalised with abdominal pain and swelling. Depending on the orientation of the eggs within the tissue some were observed as having a distinct lateral spine (as shown in the image). What is the scientific name of the parasite that produces eggs with this morphology? a. Schistosoma japonicum b. Schistosoma mansoni c. Schistosoma haematobium d. Schistosoma intercalatum e. Schistosoma mekongi 22. Schistosoma spp. belong to the Class Trematoda which also includes other important parasites of humans such as Fasciola, Clonorchis and Opisthorchis spp.. Which of the following is not true about Schistosoma spp. compared to the other members of the Trematoda? a. These parasites have complex life cycles involving mollusc and vertebrate (including humans) hosts b. These parasites are acoelomates (having no body cavity) c. These parasites are flatworms belonging to the Phylum Platyhelminthes d. These parasites are hermaphroditic (having both female and male organs) e. All of the available options Specimen for Question 24 24. The image shows two partially embryonated nematode eggs (x400 magnification) in a wet mount of a formol-ethyl acetate concentrated stool sample from a five-year old child as part of a health screen. The child has been suffering from irritability and sleep problems and intense itching around the anus. Based on the morphology of the eggs and the additional information provided which parasite is the child infected with? a. Fasciola hepatica b. Enterobius vermicularis c. Taenia solium d. Trichuris trichiura e. Schistosoma mansoni Specimen for Question 27 27. The image shows a large unembryonated trematode egg containing a granular material, and with an open operculum in an unstained wet faecal smear (x400 magnification). No clinical background was provided for this sample. Based on the morphology of the egg shown, which of the following genera of parasites does this egg belong to? a. Schistosoma  b. Fasciola c. Trichiuris d. Enterobius e. Necator Specimen for Questions 28 and 29. 28. The image shows a specimen of parasitic nematode worm removed from a number of locally caught marine fish as part of a parasitological survey following a number of small outbreaks of gastrointestinal symptoms in patients who had admitted to having recently eaten sushi in a number of seafood and Japanese restaurants in Kuala Lumpur, Malaysia. Based on clinical evidence and histological examination of cross sections of the worm, patients were diagnosed with Anisakiasis. Which Order of nematodes does this parasite belong to? a. Aphelenchida b. Toxocaridae c. Strongylida d. Anisakidae e. Ascaridida 29. As part of the parasitological survey mentioned in Question 19, 240 fishes were examined. Of these, 192 had the parasite, which is a prevalence of 80%. The mean intensity of infection was 32. What is the correct way of calculating the mean intensity of an infection or disease? a. Mean intensity of infection = number of individuals examined/number of infected individuals x 100 b. Mean intensity of infection = total number of parasites/number of infected hosts c. Mean intensity of infection = number of infected individuals/number of individuals examined x 100 d. Mean intensity of infection = number of infected hosts/total number of parasites e. Mean intensity of infection = number of infected individuals x number of individuals examined Specimen for Question 30  A B 30. The photo shows a cross-section through an adult male nematode. What are the structures labelled A and B in the cross-section? a. Testes and Vas deferens b. Pseuodocoelum and testes c. Cuticle and testes d. Longitudinal muscles and intestine e. Longitudinal muscles and Vas deferens ☺ END OF THE TEST ☺