Question 1

Which of the following statements best explains why cyanobacteria are considered crucial to the evolution of life on Earth?

Accepted Answer

They transformed the early anaerobic atmosphere into an oxygen-containing atmosphere through oxygenic photosynthesis.

Question 2

A microbiologist isolates a prokaryote from a hot spring that thrives at 90°C, has branched hydrocarbon chains in its membrane, and lacks peptidoglycan. Which group does this organism most likely belong to?

Accepted Answer

Thermophilic archaea

Question 3

Which of the following best describes the process of binary fission in prokaryotes?

Accepted Answer

A process where the cell elongates, replicates its DNA, forms a cross wall, and divides into two daughter cells.

Question 4

Which of the following equations correctly represents the conversion of carbon dioxide and hydrogen gas to methane by methanogenic archaea?

Accepted Answer

$$\mathrm{CO_2$ + 4H_2 \rightarrow CH_4$ + 2H_2O}$$

Question 5

A patient presents with a bullseye rash after a tick bite. Which bacterial group is most likely responsible for this infection?

Accepted Answer

Spirochetes

Question 6

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

Accepted Answer

They lack a cell wall and are the smallest free-living cells.

Question 7

Which of the following best explains why Bacillus thuringiensis is important in agriculture?

Accepted Answer

It produces a toxin used as an insecticide.

Question 8

Which of the following arrangements results from division in two perpendicular planes and separation of daughter cells?

Accepted Answer

Tetrads

Question 9

A soil bacterium is found to form branching filaments and is used in the production of antibiotics. To which group does it most likely belong?

Accepted Answer

Actinomycetes

Question 10

Which of the following is true regarding the cell wall composition of Archaea?

Accepted Answer

They lack true peptidoglycan and have unique membrane lipids.

Question 11

Which of the following genera is associated with nitrogen fixation in root nodules of legumes?

Accepted Answer

Rhizobium

Question 12

Which of the following best describes the main difference between the life cycles of Myxobacteria and typical binary fission?

Accepted Answer

Myxobacteria form multicellular fruiting bodies under nutrient depletion.

Question 13

Which of the following is a characteristic of Euryarchaeota but not of Bacteria?

Accepted Answer

Ability to produce methane from carbon dioxide and hydrogen.

Question 14

Which of the following is a common misconception about the pathogenicity of Archaea?

Accepted Answer

Archaea are not known to cause disease in humans.

Question 15

Which of the following bacteria is most likely to be found colonizing the respiratory passages of cystic fibrosis patients and is known for its metabolic versatility?

Accepted Answer

Burkholderia

Question 16

Which of the following best describes the role of heterocysts in cyanobacteria?

Accepted Answer

They are specialized cells for nitrogen fixation.

Question 17

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

Accepted Answer

They move in a corkscrew motion due to axial filaments.

Question 18

Which of the following equations best represents the process of nitrogen fixation by cyanobacteria?

Accepted Answer

$$\mathrm{N_2$ + 8H^+ + 8e^- + 16ATP \rightarrow 2NH_3 + H_2$ + 16ADP + 16P_i}$$

Question 19

Which of the following is true about the class Gammaproteobacteria?

Accepted Answer

It includes Pseudomonas, which is known for its polar flagella and ability to cause urinary tract infections.

Characterizing and Classifying Prokaryotes: Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards