Question 1

Which of the following best describes the main difference between gram-positive and gram-negative bacteria?

Accepted Answer

Gram-positive bacteria have a thick layer of peptidoglycan in their cell wall, while gram-negative bacteria have a thin layer and an outer membrane.

Question 2

A scientist discovers a prokaryote living in a hot spring with temperatures above 90°C and high salt concentrations. To which domain is this organism most likely to belong?

Accepted Answer

Domain Archaea

Question 3

Which structure allows certain bacteria to survive harsh conditions such as extreme heat, drought, or chemical exposure?

Accepted Answer

Endospore

Question 4

Which of the following is a correct pairing of nutritional mode and its energy and carbon source in prokaryotes?

Accepted Answer

Photoautotroph: sunlight for energy, $$CO_2$$ for carbon

Question 5

Which external feature of prokaryotes is primarily responsible for attachment to surfaces and the formation of biofilms?

Accepted Answer

Fimbriae

Question 6

A patient is infected with a bacterium that releases proteins into its environment, causing tissue damage. What type of toxin is this bacterium producing?

Accepted Answer

Exotoxin

Question 7

Which of the following best explains why prokaryotic populations can adapt rapidly to environmental changes?

Accepted Answer

They reproduce quickly, generating high genetic variation.

Question 8

Which group of bacteria is the only prokaryotic group capable of oxygen-generating photosynthesis?

Accepted Answer

Cyanobacteria

Question 9

A sewage treatment facility uses bacteria to break down organic waste. This process is an example of which of the following?

Accepted Answer

Bioremediation

Question 10

Which of the following statements about biofilms is correct?

Accepted Answer

Biofilms are complex communities of microbes that are difficult to eradicate and can cause medical and environmental problems.

Question 11

Which of the following is NOT a characteristic used to distinguish between the domains Bacteria, Archaea, and Eukarya?

Accepted Answer

Presence of mitochondria

Question 12

Which of the following best describes the role of plasmids in prokaryotic cells?

Accepted Answer

They are small, circular DNA molecules that can carry genes for antibiotic resistance.

Question 13

A scientist is studying a prokaryote that thrives in the absence of oxygen and produces methane as a metabolic byproduct. This organism is most likely a:

Accepted Answer

Methanogen

Question 14

Which of the following is a real-world example of the use of prokaryotes in industry?

Accepted Answer

Using bacteria to clean up oil spills through bioremediation

Question 15

Which of the following best explains why we are not aware of the trillions of bacterial cells living in and on our bodies?

Accepted Answer

Most bacteria are microscopic and do not cause harm under normal conditions.

Question 16

Which of the following is NOT a common prokaryotic cell shape?

Accepted Answer

Cuboidal

Question 17

A pathogenic bacterium is found to cause disease only when its cell wall is broken down by the immune system, releasing toxic lipids. What type of toxin is responsible?

Accepted Answer

Endotoxin

Question 18

Which of the following features is found in both Archaea and Eukarya, but not in Bacteria?

Accepted Answer

Presence of introns in some genes

Question 19

Which of the following is a correct example of a chemoheterotroph?

Accepted Answer

Salmonella typhimurium, which obtains both energy and carbon from organic compounds

Question 20

Which of the following adaptations allows prokaryotes to colonize a wide variety of environments, including extreme ones?

Accepted Answer

Unparalleled nutritional diversity

Microbial Life: Prokaryotes and Protists – Structure, Diversity, and Ecological Roles

Study Guide - Practice Questions

Study Guide - Flashcards