Deck 26: Bacteria and Archaea

Question 1

Some researchers have begun attempting to clean up oil spills by adding nonindigenous microbial hydrocarbon degraders to the spill, in the hope that these bacteria will neutralize the dangerous chemicals in the spill. This is an example of ________.

A) bioremediation via fertilization
B) seeding
C) production of a new antibiotic
D) use of extremophiles for cleanup of organic solvents

Answer 1

B

Question 2

Which of the following traits do archaeans and bacteria share?

A) composition of the cell wall
B) lack of a nuclear envelope
C) presence of plasma membrane
D) both A and B
E) both B and C

Answer 2

E

Question 3

A water sample from a hot thermal vent contained a single-celled organism that had a cell wall but lacked a nucleus. What is its most likely classification?

A) Eukarya
B) Archaea
C) Animalia
D) Protista
E) Fungi

Answer 3

B

Question 4

Prokaryotes are classified as belonging to two different domains. What are the domains?

A) Bacteria and Eukarya
B) Archaea and Monera
C) Eukarya and Monera
D) Bacteria and Protista
E) Bacteria and Archaea

Question 5

A prokaryote that obtains energy from light is a(n) ________.

A) chemotroph
B) phototroph
C) autotroph and phototroph
D) heterotroph and chemotroph
E) autotroph, phototroph, and chemotroph

Question 6

You need to identify the major type of bacteria living on the shower curtain in your bathroom and find out what they use as a food source. What is the most efficient method for answering this question?

A) enrichment culture
B) producing a molecular phylogeny
C) direct sequencing
D) Enrichment culture and direct sequencing are equally efficient methods.

Question 7

Which of the following describe all existing bacteria?

A) pathogenic, omnipresent, morphologically diverse
B) extremophiles, tiny, abundant
C) small, harmful, fast-growing
D) tiny, ubiquitous, metabolically diverse
E) morphologically diverse, metabolically diverse, extremophiles

Question 8

What is the goal of bioremediation?

A) to improve human health with the help of living organisms such as bacteria
B) to clean up areas polluted with toxic compounds by using bacteria
C) to improve soil quality for plant growth by using bacteria
D) to improve bacteria for production of useful chemicals
E) to kill pathogenic bacteria with the use of antibiotics

Question 9

Chemicals, secreted by soil fungi, which inhibit the growth of bacteria, are known as ________.

A) antibodies
B) aflatoxins
C) hallucinogens
D) antigens
E) antibiotics

Question 10

An organic solvent widely used in industrial processes, 1,1,1-trichloroethane (TCA), is a major environmental pollutant affecting human health and damaging the ozone layer. Recently, researchers isolated the first bacteria able to degrade TCA. They found that the bacteria use hydrogen as an electron donor, TCA as an electron acceptor, and acetate as a carbon source. Based on the preceding information, deduce the method used to isolate these bacteria.

A) Gram staining
B) enrichment culture
C) direct sequencing
D) seeding

Question 11

Microbiologists use the Gram stain to aid in the identification of bacteria. What is the major difference between Gram-positive and Gram-negative bacteria?

A) structure of nucleotides in the plasma membrane
B) presence or absence of muramic acid in the cell wall
C) presence or absence of peptidoglycan in the cell wall
D) presence or absence of outer plasma membrane

Question 12

You might be interested to know how many different types of bacteria live on the shower curtain in your bathroom. What is the most efficient method for finding out?

A) producing a molecular phylogeny
B) enrichment culture
C) direct sequencing
D) Enrichment culture and direct sequencing are equally efficient methods.

Question 13

A prokaryote that obtains energy and carbon as it decomposes dead organisms is a(n) ________.

A) autotroph
B) chemotroph
C) autotroph and phototroph
D) heterotroph and chemotroph
E) autotroph, phototroph, and chemotroph

Question 14

Biologists sometimes divide living organisms into two groups: autotrophs and heterotrophs. These two groups differ in ________.

A) their sources of energy
B) their electron acceptors
C) their mode of nutrition
D) the way that they generate ATP

Question 15

Broad-spectrum antibiotics inhibit the growth of most intestinal bacteria. Consequently, assuming that nothing is done to counter the reduction of intestinal bacteria, a hospital patient who is receiving broad-spectrum antibiotics is most likely to become ________.

A) unable to fix carbon dioxide
B) antibiotic-resistant
C) unable to fix nitrogen
D) unable to synthesize peptidoglycan
E) deficient in certain vitamins and nutrients

Question 16

What organisms are most numerous on Earth?

A) eukaryotes
B) archaea
C) prokaryotes
D) plants
E) insects

Question 17

Carl Woese and collaborators identified two major branches of prokaryotic evolution. What was the basis for dividing prokaryotes into two domains?

A) microscopic examination of staining characteristics of the cell wall
B) metabolic characteristics such as the production of methane gas
C) metabolic characteristics such as chemoautotrophy and photosynthesis
D) genetic characteristics such as ribosomal RNA sequences
E) ecological characteristics such as the ability to survive in extreme environments

Question 18

To establish a link between a specific bacterium and a skin disease, researchers have shown that the bacterium was present in sick persons but not in healthy individuals. They isolated the bacterium in a pure culture and demonstrated that experimental healthy animals injected with this culture became sick. What other experiment do researchers need to perform to be absolutely sure that the bacterium is responsible for the disease?

A) demonstrate that the bacterium belongs to the pathogenic lineage
B) demonstrate that the bacterium is not able to live outside of humans or animals
C) isolate bacterium from an infected sick animal and demonstrate that it is the same bacterium as the one used for infection

Question 19

Imagine that you are given some chemoorganotrophic bacteria to grow. What should you use as a source of energy for this type of bacteria?

A) light
B) methane
C) ammonia
D) hydrogen sulfide
E) sugar

Question 20

A prokaryote that obtains carbon and energy by ingesting prey is a(n) ________.

A) autotroph
B) chemotroph
C) autotroph and phototroph
D) heterotroph and chemotroph
E) autotroph, phototroph, and chemotroph

Question 21

A bacterium was grown in two test tubes filled with media rich in glucose. One tube was sealed to produce anaerobic conditions, and the other was not. A third uninoculated, unsealed tube was used as a control. Glucose utilization by this bacterium causes acid production, which is indicated by a lightening of the media color. If the bacterium is able to produce ATP only by aerobic respiration, we expect lightening of media in ________.

A) the sealed tube only
B) the unsealed tube only
C) the sealed and unsealed tubes only
D) the control tube only
E) all three tubes

Question 22

You run an osteology lab, where students are able to study the bone structure of various species. To produce clean bones, you introduce insects and bacteria to remove all remaining flesh. Which bacteria would be the best purchase for your lab?

A) Spirochaetes
B) Actinobacteria
C) Chlamydiae
D) Cyanobacteria
E) Proteobacteria

Question 23

Bacteria able to perform the NH4+ + NO2− → N2 + 2H2O reaction have been discovered in laboratory bioreactors and wastewater treatment systems. Researchers predicted that these bacteria should exist in oceans. They measured the concentration of NH4+, NO2−, NO3−, and O2 in the Black Sea as a function of water depth (M. Kuypers et al. 2003 Anaerobic ammonium oxidation by anammox bacteria in the Black Sea. Nature 422:608-11) to determine where in the sea the bacteria might live. By analyzing data presented in the accompanying figure, at what depth would you expect to find the bacteria? (Note: In the figure, different scales are used to show concentrations of NH4+, NO2−, NO3−, and O2.)

A) in the top 5 meters
B) in the top 50 meters
C) at a depth of 75 meters
D) at a depth of 92 meters
E) below 100 meters

Question 24

What kind of molecules serve as electron acceptors in cellular respiration?

A) water
B) polar molecules
C) molecules with high potential energy
D) molecules with low potential energy
E) molecules in an excited state

Question 25

Researchers have found a new type of bacteria, and they want to determine its phylum. What would be the most reliable method to do so?

A) conducting a Gram-stain test
B) performing an analysis of metabolic pathways
C) determining the ribosomal RNA sequence of the bacteria
D) analyzing the morphological characteristics of the bacteria

Question 26

Multicellularity and large body size of eukaryotic organisms require high metabolic rates and efficient ATP production by aerobic respiration. How did bacteria change Earth's atmosphere to enable aerobic respiration?

A) Oxygenic photosynthesis by cyanobacteria significantly increased the amount of oxygen in the atmosphere.
B) Splitting of water during anaerobic respiration by cyanobacteria dramatically increased the amount of oxygen in the atmosphere.
C) Nitrogen fixation by cyanobacteria decreased the amount of nitrogen in the atmosphere, leading to the simultaneous increase of oxygen.
D) Anaerobic respiration by cyanobacteria increased the amount of oxygen in the atmosphere by reducing the amount of iron oxides that were able to react instantly with oxygen.

Question 27

During cellular respiration, some bacteria use methane (CH4) as an electron donor and oxygen (O2) as an electron acceptor. What is the name for this group of bacteria?

A) methanogens
B) methanotrophs
C) organotrophs
D) nitrifiers

Question 28

The purple nonsulfur bacterium Rhodospirillum grows best as a photoheterotroph. What are the most favorable sources of energy and carbon for this bacterium?

A) methane and carbon dioxide
B) fructose and light
C) light and carbon dioxide
D) glucose

Question 29

Which of the following extremophiles might researchers most likely use as a model for the earliest organisms on Earth?

A) a bacterium capable of living at extremely high salinity
B) a bacterium found on another planet or moon
C) an archaean capable of surviving in the polar ice caps
D) an anaerobic archaean species
E) a bacterium that thrives in a highly acidic environment

Question 30

Which of the following groups is characterized by unusual flagella contained within a structure called the outer sheath?

A) Spirochaetes/Spirochetes
B) Proteobacteria
C) Firmicutes
D) Chlamydiales
E) Euryarchaeota

Question 31

A biologist trying to determine the mechanism of adenosine triphosphate (ATP) production in a newly discovered bacterium provides several different substrates on which the bacteria can feed. Which of the following results would indicate that the species uses fermentation to produce ATP?

A) The bacteria utilize glucose and produce carbon dioxide as a by-product of respiration.
B) After the bacteria break down their substrate, the biologist notices a rotten egg smell.
C) The biologist discovers that the bacteria are able to produce organic molecules by metabolizing methane.
D) After exposure to amino acids, the bacteria produce a smell like rotting flesh.

Question 32

Which of the following obtain energy by oxidizing inorganic substances to obtain energy that is used, in part, to fix carbon dioxide?

A) photoautotrophs
B) photoheterotrophs
C) chemoautotrophs
D) chemoheterotrophs that perform decomposition
E) parasitic chemoheterotrophs

Question 33

A newly discovered organism is found to use sulfide (S2−) for aerobic respiration and carbon dioxide (CO2) from the air as a source of carbon, much like a plant. This organism must be a ________.

A) photoautotroph
B) chemoorganoautotroph
C) photoheterotroph
D) chemolithotrophic heterotroph
E) chemolithoautotroph

Question 34

You acquire a soil sample and run an enrichment culture on it. You provide the organisms in the culture with all of the ingredients required for growth except for nitrogen. What result do you expect to have at the end of your experiment?

A) Nitrogen-fixing bacteria will significantly outnumber those incapable of fixing nitrogen.
B) Nitrogen-fixing bacteria will not be present in the culture.
C) Nitrogen-fixing bacteria will be present but not at significantly greater numbers than non-nitrogen-fixing species.
D) Nitrogen-fixing bacteria will be present, but will be significantly outnumbered by non-nitrogen-fixing species.

Question 35

You have found a new prokaryote. What line of evidence would support your hypothesis that the organism is a cyanobacterium?

A) It is able to form colonies and produce oxygen.
B) It is an endosymbiont.
C) It forms chains called mycelia.
D) You determine that it can cause Lyme disease.
E) It lacks cell walls.

Question 36

Plantlike photosynthesis that releases oxygen (O2) occurs in ________.

A) cyanobacteria
B) chlamydias
C) archaea
D) actinomycetes
E) chemoautotrophic bacteria

Question 37

What is the characteristic feature of the Chlamydiales phylum?

A) unusual flagella
B) formation of colonies
C) rod shape
D) parasitic life cycle

Question 38

When some bacteria use lactose as a source of energy, they produce propionic acid and carbon dioxide. What is the name for this process?

A) fermentation
B) cellular respiration
C) chemical synthesis
D) photosynthesis
E) carbon fixation