Question 1

Which of the following best describes the role of normal microbiota in human health?

Accepted Answer

They prevent the growth of pathogens and produce essential vitamins such as B and K.

Question 2

Which of the following statements about biofilms is CORRECT?

Accepted Answer

Biofilms can protect mucous membranes and provide food in aquatic ecosystems.

Question 3

Which of the following is NOT a domain in the three-domain system of classification?

Accepted Answer

Virus

Question 4

Which structure allows prokaryotes to transfer genetic material during conjugation?

Accepted Answer

Sex pilus

Question 5

Which of the following best explains why cells are small in size?

Accepted Answer

To maximize the ratio of surface area to volume for efficient exchange of nutrients and waste.

Question 6

Which metabolic classification describes an organism that uses sunlight for energy and CO$$_2 as a $$carbon source?

Accepted Answer

Photoautotroph

Question 7

Which of the following statements about Gram-negative bacteria is TRUE?

Accepted Answer

They have two membranes and a thin peptidoglycan layer.

Question 8

Which of the following is a function of cyanobacteria in the environment?

Accepted Answer

Photosynthesis and nitrogen fixation

Question 9

Which of the following is a correct statement about viruses?

Accepted Answer

Viruses are acellular and require a host cell for replication.

Question 10

Which scientist is credited with disproving the theory of spontaneous generation using S-shaped flasks?

Accepted Answer

Louis Pasteur

Question 11

Which of the following best describes the process of bioremediation?

Accepted Answer

Using microbes to remove toxic substances from the environment

Question 12

Which of the following is a distinguishing feature of fungi compared to bacteria?

Accepted Answer

Fungi have chitin cell walls and a nucleus.

Question 13

Which of the following is an example of an emerging infectious disease?

Accepted Answer

A disease that has recently increased in incidence or geographic range

Question 14

Which of the following is a correct pairing of a microbe and its role in human health or disease?

Accepted Answer

Staphylococcus aureus – normal skin flora, but can cause infections

Question 15

Which of the following statements about the Germ Theory of Disease is TRUE?

Accepted Answer

It was supported by Koch’s postulates, which linked specific microbes to specific diseases.

Question 16

Which of the following best describes the process of endosymbiosis in eukaryotic evolution?

Accepted Answer

A eukaryotic cell engulfed a prokaryote, which became an organelle such as a mitochondrion or chloroplast.

Question 17

Which of the following is a plausible reason why bacteria in biofilms are often resistant to antibiotics?

Accepted Answer

Biofilms provide a protective matrix that limits antibiotic penetration.

Question 18

Which of the following best describes the difference between light microscopy and electron microscopy?

Accepted Answer

Light microscopy uses visible light and has a lower resolution than electron microscopy, which uses shorter wavelengths for higher resolution.

Question 19

Which of the following is a correct statement about the metabolic diversity of prokaryotes?

Accepted Answer

Some prokaryotes can use inorganic molecules as an energy source and CO$$_2 as a $$carbon source.

Question 20

Which of the following is a correct description of the function of fungal hyphae?

Accepted Answer

They form networks (mycelia) that absorb nutrients and may trap prey.

Introduction to Microbiology: The Microbial World and You

Study Guide - Practice Questions