This set of Microbiology Multiple Choice Questions & Answers (MCQs) focuses on “Diseases Caused by Protozoa”.
1. Animals that are routinely infected with a protozoan or parasite are termed as _______________
a) definitive host
b) intermediate host
c) reservoir host
d) parasitic host
Explanation: An animal (or human) that is routinely infected with a protozoan or parasite which can also infect humans is termed as a reservoir host.
2. For the malaria protozoa, mosquitoes are the definitive host.
Explanation: For the malaria protozoa, the mosquito is the definitive host, and humans or other vertebrates are the intermediate hosts.
3. Laboratory diagnosis of Entamoeba histolytica depends on identification in the ___________
Explanation: Laboratory diagnosis of Entamoeba histolytica depends on identification in the stools. Search for the amoeba should be made as soon as possible after the stool is passed to be sure of the presence of living, motile forms.
4. African sleeping sickness is caused by which of the following protozoa?
a) Entamoeba histolytica
b) Trypanosoma gambiense
c) Leishmania donovani
d) Plasmodium vivax
Explanation: African sleeping sickness is caused by Trypanosoma gambiense and is transmitted by flying bite.
5. Most commonly Plasmodium ovale and Plasmodium malariae causes malaria in humans.
Explanation: Of the four species of Plasmodium protozoa that cause malaria in humans, P. falciparum and P. vivax are the two that most commonly cause infections.
6. After how many days of infection by mosquitoes do the symptoms for malaria occur?
Explanation: Symptoms usually occur 10 to 16 days after infection by the mosquitoes.
7. The schizonts enter which body part?
Explanation: The sporozoites quickly enter the liver, where they divide and develop into multinucleated forms known as schizonts.
8. How much time does it take for the rupture of infected erythrocytes with P. vivax?
a) 24 h
b) 48 h
c) 72 h
d) 96 h
Explanation: The rupture of infected erythrocytes at the completion of schizogony occurs every 48 h with P. vivax and P. ovale.
9. The disease espundia is caused by which of the following protozoa?
a) Leishmania brasiliensis
b) Leishmania donovani
c) Leishmania tropica
d) Phlebotomus sp
Explanation: Leishmania brasiliensis causes the disease espundia which can then cause the infection for the disease leishmaniasis.
10. Leishmania organism are transmitted to humans by ______________
b) tsetse flies
Explanation: Leishmania organism are transmitted to humans by the bites of sandflies (genus Phlebotomus) harbored by dogs and other animals that serve as reservoirs for the parasites.
11. What is the incubation period for kala azar disease?
a) 24 h
b) 1 month
c) 2-4 months
d) 7 days
Explanation: Clinically, kala azar has a variable incubation period, usually 2 to 4 months. Onset may be gradual or sudden, and the source of the disease may be acute or chronic.
12. African sleeping sickness is caused by _______________
a) Trypanosoma cruzi
b) Trypanosoma gambiense
c) Trichomonas vaginalis
d) Leishmania tropica
Explanation: African sleeping sickness is caused by Trypanosoma gambiense and Trypanosoma rhodesiense.
13. Chagas’ disease is transmitted to humans by ________________
a) tsetse fly
c) reduviid bugs
Explanation: T.cruzi, the causative agent of Chagas’ disease is transmitted to humans by reduviid bugs (Triatoma, Rhodinas, and Panstrongylus), which are intermediate hosts as well as vectors for the parasites.
14. Where are the protozoa present during the acute stage of Chagas’ disease?
Explanation: T. cruzi is present in the blood during the acute stage of Chagas’ disease. Fatality is due to a meningoencephalitis or myocardial failure.
Sanfoundry Global Education & Learning Series – Microbiology.
To practice all areas of Microbiology, here is complete set of 1000+ Multiple Choice Questions and Answers.