Question 1

Which life stage of protozoan parasites is most likely to survive harsh environmental conditions such as changes in pH, nutrient availability, or temperature?

Accepted Answer

Cyst

Question 2

A hiker develops severe diarrhea after drinking untreated stream water. Microscopy reveals a protozoan with two nuclei and multiple flagella, but no mitochondria. Which organism is most likely responsible?

Accepted Answer

Giardia intestinalis

Question 3

Which of the following best describes the movement mechanism of an amoeba?

Accepted Answer

Shape-changing pseudopods

Question 4

A patient presents with a brain abscess after swimming in a warm freshwater lake. Which protozoan is the most likely cause?

Accepted Answer

Naegleria fowleri

Question 5

Which of the following protozoan parasites is transmitted by the tsetse fly and causes sleeping sickness?

Accepted Answer

Trypanosoma brucei

Question 6

Which protozoan parasite is associated with congenital defects when a pregnant woman is exposed to cat feces?

Accepted Answer

Toxoplasma gondii

Question 7

Which of the following best explains why Plasmodium falciparum infections cause cycling fevers every 48-72 hours?

Accepted Answer

Lysis of red blood cells releases merozoites

Question 8

A soldier returning from the Middle East presents with disfiguring skin lesions. Which vector and parasite are most likely involved?

Accepted Answer

Sandfly and Leishmania species

Question 9

Which of the following is NOT caused by a protozoan parasite?

Accepted Answer

Histoplasmosis

Question 10

Which protozoan parasite is most likely to cause severe diarrhea in people participating in outdoor water sports?

Accepted Answer

Cryptosporidium parvum

Question 11

Which of the following best describes the life cycle of Giardia intestinalis?

Accepted Answer

Alternates between a swimming trophozoite and an infective cyst

Question 12

A patient with a history of untreated water exposure presents with eye pain and vision loss. Which protozoan is most likely responsible?

Accepted Answer

Acanthamoeba species

Question 13

Which of the following protozoan parasites lacks a cyst form and is primarily transmitted as a sexually transmitted disease?

Accepted Answer

Trichomonas vaginalis

Question 14

Which of the following is the correct sequence of life cycle stages for Plasmodium species in humans?

Accepted Answer

Sporozoite → Merozoite → Gametocyte

Question 15

Which of the following best explains why malaria remains a major global health problem?

Accepted Answer

High transmission rates by Anopheles mosquitoes and drug resistance

Question 16

A patient presents with ulcerative colitis and liver abscesses after traveling to a developing country. Which protozoan is most likely responsible?

Accepted Answer

Entamoeba histolytica

Question 17

Which of the following statements about apicomplexan parasites is TRUE?

Accepted Answer

They have a complex of organelles at their apical tips for penetrating host cells

Question 18

Which of the following equations best represents the exponential growth of protozoan parasites in a host, assuming unlimited resources?

Accepted Answer

$$N(t) = N_0$ e$$^{rt}$$

Question 19

A city in the Americas reports an outbreak of Chaga’s disease. Which vector and protozoan are responsible?

Accepted Answer

Triatomine bug and Trypanosoma cruzi

Question 20

Which of the following best describes the transmission of Cryptosporidium parvum?

Accepted Answer

Ingestion of oocysts from contaminated water

lec 17

Study Guide - Practice Questions

Study Guide - Flashcards