Question 1

Which of the following best describes a key structural difference between prokaryotic and eukaryotic cells?

Accepted Answer

Eukaryotic cells have a membrane-bound nucleus, while prokaryotic cells lack a nucleus and their DNA is found in the cytoplasm.

Question 2

Which of the following statements about the metabolic diversity of bacteria and archaea is correct?

Accepted Answer

Bacteria and archaea can be autotrophs or heterotrophs, utilizing a wide range of energy sources.

Question 3

Which of the following is a major ecological role of nitrogen-fixing bacteria?

Accepted Answer

They convert atmospheric $$\mathrm{N_2$}$$ into forms usable by plants, supporting plant growth and ecosystem productivity.

Question 4

What is the primary reason soil bacteria and fungi produce antibiotic compounds?

Accepted Answer

To reduce competition with other soil-dwelling organisms.

Question 5

Which of the following statements correctly differentiates between bacteria and archaea?

Accepted Answer

Bacteria have peptidoglycan in their cell walls, while archaea do not.

Question 6

Which type of bacteria is more susceptible to penicillin, and why?

Accepted Answer

Gram-positive bacteria, because penicillin targets their thick peptidoglycan cell wall.

Question 7

Which of the following best describes extremophiles?

Accepted Answer

Bacteria and archaea that thrive in high-salt, high-temperature, low-temperature, or high-pressure habitats.

Question 8

Why are extremophiles of interest in commercial applications?

Accepted Answer

They produce enzymes that function at extreme temperatures, useful in industrial processes.

Question 9

Which of the following is true about the microbiome?

Accepted Answer

It refers to the community of microbes that naturally inhabit a particular area.

Question 10

What type of selection is likely to occur when a new pathogenic bacterial species is introduced to a host species, considering virulence?

Accepted Answer

Directional selection

Question 11

Which of the following statements about the central dogma machinery in archaea is correct?

Accepted Answer

Archaea have central dogma machinery more similar to eukaryotes than to bacteria.

Question 12

Which of the following is NOT a characteristic shared by all cells (prokaryotic and eukaryotic)?

Accepted Answer

Presence of a membrane-bound nucleus

Question 13

Which of the following best describes the role of cyanobacteria during the Precambrian?

Accepted Answer

They were primarily responsible for oxygenating the atmosphere.

Question 14

Which of the following statements about Gram staining is correct?

Accepted Answer

Gram-positive bacteria stain purple due to their thick peptidoglycan layer.

Question 15

Which of the following is a plausible consequence if a bacterial strain replicates too quickly within a host?

Accepted Answer

The host may die before the bacteria can be transmitted, reducing the strain's evolutionary success.

Question 16

Which of the following is true about photoautotrophs among prokaryotes?

Accepted Answer

Photoautotrophs generate energy from sunlight through photosynthesis, but this process has not been reported in archaea.

Question 17

Which of the following is a correct statement about the morphology of bacteria and archaea?

Accepted Answer

Bacteria and archaea are morphologically diverse, including shapes such as cocci, bacilli, and spirilla.

Question 18

Which of the following is a plausible reason why antibiotics often target the synthesis of peptidoglycan?

Accepted Answer

Peptidoglycan is unique to bacterial cell walls, making it an effective target for antibiotics.

Question 19

Which of the following best describes mutualistic relationships involving prokaryotes?

Accepted Answer

Mutualistic prokaryotes, such as nitrogen-fixing bacteria, benefit their hosts by providing essential nutrients.

Prokaryotic Diversity: Structure, Metabolism, and Ecological Roles of Bacteria and Archaea

Study Guide - Practice Questions