Question 1

Which of the following is a core characteristic that distinguishes eukaryotic microbes from prokaryotic microbes?

Accepted Answer

Their DNA is enclosed within a nucleus.

Question 2

Which group of eukaryotic microbes is primarily responsible for producing much of Earth's oxygen and forming the base of ocean food webs?

Accepted Answer

Algae

Question 3

A patient presents with severe diarrhea, malabsorption, and weight loss after returning from a camping trip. Stool antigen testing confirms the presence of a flagellated protozoan with two nuclei and a ventral disc. What is the most likely causative agent?

Accepted Answer

Giardia duodenalis

Question 4

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

Accepted Answer

Alternates between trophozoite and infectious cyst forms

Question 5

Which of the following is the primary mode of transmission for Zika virus?

Accepted Answer

Bite of infected Aedes mosquitoes

Question 6

A researcher is studying a protozoan that divides by mitosis, has a ventral disc, and is pear-shaped with two nuclei. Which structure allows this organism to attach to the intestinal mucosa?

Accepted Answer

Ventral disc

Question 7

Which of the following invertebrates acts as a vector by transmitting pathogens that develop or multiply within them before being passed to a new host?

Accepted Answer

Mosquito

Question 8

Which of the following is a distinguishing feature of kinetoplastid protozoa, such as Trypanosoma, but not Giardia or Trichomonas?

Accepted Answer

Presence of a kinetoplast containing mitochondrial DNA

Question 9

A child in a daycare center develops giardiasis. Which of the following is the most likely source of infection?

Accepted Answer

Swallowing water or objects contaminated with Giardia cysts

Question 10

Which of the following laboratory methods is considered most sensitive for diagnosing Giardia infection?

Accepted Answer

Stool antigen detection assays or nucleic acid amplification tests (NAAT)

Question 11

Which of the following best explains why collecting three stool samples on different days increases the sensitivity of Giardia detection by microscopy?

Accepted Answer

Giardia is intermittently shed in stool

Question 12

Which of the following is the first-line pharmacological treatment for giardiasis?

Accepted Answer

Metronidazole

Question 13

A patient with Zika virus infection develops muscle weakness and temporary paralysis. Which neurological complication is most likely associated with this infection?

Accepted Answer

Guillain-Barré Syndrome

Question 14

Which of the following statements about Zika virus transmission is correct?

Accepted Answer

It can be transmitted sexually even by asymptomatic individuals.

Question 15

Which of the following best describes the sylvatic (rural) cycle of Zika virus transmission?

Accepted Answer

Transmission between non-human primates and forest mosquitoes

Question 16

Which of the following is a direct parasitic agent that infects humans?

Accepted Answer

Tapeworm

Question 17

Which of the following best explains why fungi are important in ecological balance?

Accepted Answer

They recycle nutrients by decomposing dead plants and animals.

Question 18

Which of the following is a characteristic of Giardia cysts that allows them to survive in the environment for months?

Accepted Answer

Thick cyst wall

Question 19

Which of the following best describes the role of mechanical vectors in disease transmission?

Accepted Answer

They physically carry pathogens from contaminated sources to food or surfaces.

Question 20

Which of the following equations best represents the process of mitosis in eukaryotic microbes?

Accepted Answer

$\mathrm{2n} \rightarrow \mathrm{2n} + \mathrm{2n}$

Eukaryotic Microbes and Invertebrate Infectious Agents: Structure, Function, and Disease

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