Question 1

Mycoplasmas differ from other bacteria in that they
A) are gram- negative.
B) are acid- fast.
C) lack a cell wall.
D) are motile.
E) grow inside host cells.

Accepted Answer

Mycoplasmas are unique among bacteria in that they lack a cell wall. This characteristic makes them resistant to certain antibiotics that target the cell wall, such as penicillin.

Question 2

All of the following bacteria are motile. Which does NOT have flagella?
A) Salmonella
B) Pseudomonas
C) spirochetes
D) Escherichia
E) helical bacteria

Accepted Answer

Spirochetes move by means of axial filaments, not flagella.

Question 3

Both Beggiatoa and the purple sulfur bacteria use H₂S. These bacteria differ in that Beggiatoa A) uses H₂S for a carbon source. B) belongs to the gammaproteobacteria. C) uses H₂S for an energy source. D) uses light energy. E) is a heterotroph.

Accepted Answer

The question is asking about the use of H₂S by Beggiatoa and purple sulfur bacteria. Both bacteria use this substance as an energy source, but none of the answer choices provide an answer that reflects that fact. Therefore, the best option is to choose the answer that is least incorrect, which is C. In general, Beggiatoa is a chemoautotroph, which means it uses inorganic compounds as an energy source and carbon dioxide as a carbon source. Purple sulfur bacteria, on the other hand, are photoautotrophs, which means they use light as an energy source and carbon dioxide as a carbon source.

Question 4

Which of the following is NOT an enteric?
A) Shigella
B) Escherichia
C) Enterobacter
D) Salmonella
E) Campylobacter

Accepted Answer

Enteric bacteria inhabit the intestinal tract, but Campylobacter is not considered an enteric because it colonizes the mucosal layer of the distal small intestine and colon instead of the large intestine.

Question 5

The nonsulfur photosynthetic bacteria use organic compounds as A) carbon sources. B) electron donors to reduce CO₂. C) oxygen sources. D) energy sources. E) electron acceptors.

Accepted Answer

The answer of The nonsulfur photosynthetic bacteria use organic compounds...

Question 6

Which of the following statements about the causative agent of Rocky Mountain spotted fever is FALSE?
A) It is transmitted by ticks.
B) It is an intracellular parasite.
C) It is gram- negative.
D) It is in the genus Rickettsia.
E) It is found in soil and water.

Accepted Answer

The causative agent of Rocky Mountain spotted fever, Rickettsia rickettsii, is not found in soil and water, but rather is transmitted by ticks. The other statements are true; R. rickettsii is an intracellular parasite, gram-negative, and is in the genus Rickettsia.

Question 7

All of the following bacteria are gram- positive. Which does NOT belong with the others?
A) Actinomyces
B) Mycobacterium
C) Listeria
D) Corynebacterium
E) Bacillus

Accepted Answer

The answer of All of the following bacteria are gram-...

Question 8

Salmonella, Shigella, Yersinia, and Serratia are all
A) gram- negative facultatively anaerobic rods.
B) endospore- forming bacteria.
C) pathogens.
D) fermentative.
E) gram- positive aerobic cocci.

Accepted Answer

Salmonella, Shigella, Yersinia, and Serratia are all gram-negative facultatively anaerobic rods and are commonly associated with causing infections in humans. They are often referred to as "Enterobacteriaceae" due to their shared characteristics and ability to ferment sugars. They are not endospore-forming, gram-positive aerobic cocci, or solely fermentative bacteria.

Question 9

Caulobacter are different from most bacteria in that they
A) have stalks.
B) are gram- positive.
C) are gram- negative.
D) are motile.
E) lack cell walls.

Accepted Answer

Caulobacter are known for their unique feature of having stalks, which are extensions of the cell membrane and cell wall used for attachment to surfaces and nutrient uptake. They are gram-negative bacteria and are also motile. While some bacterial species do lack cell walls, this is not a distinguishing feature of Caulobacter.

Question 10

Which one of the following bacteria does NOT belong with the others?
A) Escherichia
B) Bacillus
C) Lactobacillus
D) Streptococcus
E) Staphylococcus

Accepted Answer

The answer of Which one of the following bacteria does...

Question 11

A primary difference between cyanobacteria and purple and green phototrophic bacteria is A) electron donor for CO₂reduction. B) color. C) energy source. D) cell type. E) cell wall type.

Accepted Answer

Cyanobacteria use water as an electron donor for CO2 reduction, releasing oxygen, while purple and green phototrophic bacteria use other compounds like hydrogen sulfide, not producing oxygen.

Question 12

Which one of the following bacteria does NOT belong with the others?
A) Campylobacter
B) Pseudomonas
C) Salmonella
D) Bordetella
E) Burkholderia

Accepted Answer

Salmonella is a member of the Enterobacteriaceae family, while the others are not. The other bacteria listed are more commonly associated with the Pseudomonadota phylum.

Question 13

You have isolated a bacterium that grows in a medium containing only inorganic nutrients. Ammonia is oxidized to a nitrate ion. This bacterium is
A) gram- negative.
B) a photoheterotroph.
C) a photoautotroph
D) using anaerobic respiration.
E) a chemoautotroph.

Accepted Answer

The bacterium in question is capable of growing in a medium containing only inorganic nutrients and oxidizing ammonia to a nitrate ion. This indicates that it is a chemoautotroph, as it is obtaining energy from inorganic compounds and using carbon dioxide as its carbon source. It is not a photoheterotroph, photoautotroph, or using anaerobic respiration, as none of these processes involve the oxidation of ammonia to a nitrate ion. The question does not provide any information regarding the gram-stain test, so we cannot determine if the bacterium is gram-negative or not.

Question 14

Escherichia coli belongs to the
A) spirochetes.
B) actinomycetes.
C) green sulfur bacteria.
D) gram- positive bacteria.
E) proteobacteria.

Accepted Answer

Escherichia coli belongs to the proteobacteria, a large and diverse group of gram-negative bacteria that includes many pathogens and symbionts.

Question 15

Burkholderia was reclassified from the gammaproteobacteria to the betaproteobacteria because
A) it causes melioidosis.
B) it grows in disinfectants.
C) it is a gram- negative rod.
D) its rRNA sequence is similar to that of Neisseria.
E) it causes infections in cystic fibrosis patients.

Accepted Answer

Burkholderia was reclassified based on molecular phylogenetic analysis, specifically its rRNA sequence, which showed greater similarity to the betaproteobacteria like Neisseria.

Question 16

You have isolated a prokaryotic cell. The first step in identification is a(n)
A) Gram stain.
B) DNA fingerprint.
C) endospore stain.
D) flagella stain.
E) lactose fermentation test.

Accepted Answer

Gram stain is commonly used as the first step in identifying a prokaryotic cell. It allows the classification of the cell as either Gram-positive or Gram-negative, which helps to narrow down the potential identification options. Other tests such as DNA fingerprinting, endospore staining, and flagella staining are more specific and may require additional information before performing them. Lactose fermentation test is also not specific enough for initial identification.

Question 17

Which of the following is the best reason to classify Streptococcus in the Lactobacillales?
A) found in dairy products
B) Gram reaction
C) rRNA sequences
D) fermentation of lactose
E) morphology

Accepted Answer

rRNA sequences provide the most reliable and accurate information for classification and phylogenetic relationships among bacterial species.

Question 18

The crab industry needs female crabs for growing more crabs. What bacterium might be used to ensure development of female crabs and shrimp?
A) Neisseria
B) Acinetobacter
C) Gemmata
D) Wolbachia
E) Pelagibacter

Accepted Answer

Wolbachia has been used successfully to control the sex of crustaceans like crabs and shrimp. When Wolbachia infects male crustaceans, it feminizes them, resulting in the development of ovaries instead of testes. This allows for the production of more female crustaceans, which are needed to sustain the crab industry.

Question 19

You have isolated a bacterium that grows in a medium containing an organic substrate and nitrate in the absence of oxygen. The nitrate is reduced to nitrogen gas. You can be sure that this bacterium is
A) gram- positive.
B) a photoheterotroph.
C) using anaerobic respiration.
D) a photoautotroph.
E) a chemoautotroph.

Accepted Answer

The fact that the bacterium is growing in the absence of oxygen and utilizing nitrate as an electron acceptor suggests that it is using anaerobic respiration. This rules out options B, D, and E. The information given does not provide any indication of the bacterium's Gram status, so option A cannot be definitively chosen.

Question 20

Which of the following bacteria are responsible for more infections and more different kinds of infections?
A) Streptococcus
B) Neisseria
C) Salmonella
D) Pseudomonas
E) Staphylococcus

Accepted Answer

The answer of Which of the following bacteria are responsible...

Quiz 11: The Prokaryotes: Domains Bacteria and Archaea

Mycoplasmas differ from other bacteria in that they

All of the following bacteria are motile. Which does NOT have flagella?

Both Beggiatoa and the purple sulfur bacteria use H2S. These bacteria differ in that Beggiatoa

Which of the following is NOT an enteric?

The nonsulfur photosynthetic bacteria use organic compounds as

Which of the following statements about the causative agent of Rocky Mountain spotted fever is FALSE?

All of the following bacteria are gram- positive. Which does NOT belong with the others?

Salmonella, Shigella, Yersinia, and Serratia are all

Caulobacter are different from most bacteria in that they

Which one of the following bacteria does NOT belong with the others?

A primary difference between cyanobacteria and purple and green phototrophic bacteria is

Which one of the following bacteria does NOT belong with the others?

You have isolated a bacterium that grows in a medium containing only inorganic nutrients. Ammonia is oxidized to a nitrate ion. This bacterium is

Escherichia coli belongs to the

Burkholderia was reclassified from the gammaproteobacteria to the betaproteobacteria because

You have isolated a prokaryotic cell. The first step in identification is a(n)

Which of the following is the best reason to classify Streptococcus in the Lactobacillales?

The crab industry needs female crabs for growing more crabs. What bacterium might be used to ensure development of female crabs and shrimp?

You have isolated a bacterium that grows in a medium containing an organic substrate and nitrate in the absence of oxygen. The nitrate is reduced to nitrogen gas. You can be sure that this bacterium is

Which of the following bacteria are responsible for more infections and more different kinds of infections?

Both Beggiatoa and the purple sulfur bacteria use H₂S. These bacteria differ in that Beggiatoa