The most ancient type of organisms on Earth originated:

A. 4,004 years ago

B. 7,200 years ago

C. 2 million years ago
D. 3.5 billion years ago
E. 13 billion years ago

D. 3.5 billion years ago

Because they differ from all other living organisms by lacking a discrete nucleus and many other cell inclusions, Bacteria and Archaea are considered to be:
A.karyoki
B. prophasic
C. histrionic
D. prophylactic
E. prokaryotic

E. prokaryotic

Which of the following is NOT true of horizontal (lateral) transfer of genetic information?
A. transfers genes from parent to progeny
B. increases genetic diversity
C. is important for inferring phylogeny
D. can produce large genetic change
E. occurs commonly in bacteria

A. transfers genes from parent to progeny

A protein that can move protons and other ions across a cellular membrane is called a:
A.peristaltic pump
B. proton pump
C. osmotic pump
D. transferase
E. stile

B. proton pump

Archaea are resistant to damage by harsh conditions because their membrane lipids, unlike those of Bacteria and Eukaryota, have:
A. ether linkages
B. proton pumps
C. sulfhydryl linkages
D. transferases
E. cytoskeletons

A. ether linkages

Archaea have very diverse environmental requirements and tolerances. From what you have learned about them, which among the following conditions or substances do ALL archaeans require for survival and reproduction?
A. oxygen
B. water
C. moderate pH
D. moderate temperature
E. moderate salinity

B. water

Which of the following characteristics do not occur in ANY cyanobacterium?
A. undergoes photosynthesis
B. poisons natural bodies of water
C. generates oxygen
D. generates methane
E. detects the Earth's magnetic field

D. generates methane

The photosynthetic activity of cyanobacteria takes place in their:
A.thylakoids
B. mitochondria
C. pili
D. vesicles
E. vibrios

A.thylakoids

There is great diversity of shape among microbes. Form is one of the ways different taxa can be distinguished. Which of the following shapes are not found among the microbes?
A. rods
B. spheres
C. octagons
D. curved shapes
E. spirals

C. octagons

Which of the following is NOT a function of slimy mucilage in microbes?
A. protects against the host's immune system
B. binds nutrients
C. serves as a flotation device
D. prevents desiccation (drying out)
E. protects against ultraviolet radiation

E. protects against ultraviolet radiation

Microorganisms may aggregate and glue themselves to teeth to form dental plaque. This is an example of:
A. a biofilm
B. a dentifrice
C. halitosis
D. a dontoid layer
E. annealed enamel

A. a biofilm

Some individual microbes secrete small molecules that induce other microbes to settle nearby. The aggregation that forms responds collectively to stimuli and moves in common to new sites and secretes mucilage. This process is called:
A. pre-sociality
B. muco-aggregation
C. archae sociality
D. quorum sensing
E. mass-settling

D. quorum sensing

Which of the following statements does NOT describe a function of the cell walls of bacteria?

A. They maintain cell shape.
B. They prevent cross-fertilization.
C. They avoid disintegration in water with low concentrations of salt.
D. They protect against other bacteria.
E. They protect against viruses

B. They prevent cross-fertilization.

Which of the following statements is NOT true of Gram-positive bacteria?

A. They have a thicker peptidoglycan layer than do Gram-negative bacteria.
B. They turn purple when subjected to the Gram-staining process whereas Gram-negative bacteria stain pink.
C. They lack the lipopolysaccharide that Gram-negative bacteria have.
D. They fluoresce at a different color than do Gram-negative bacteria.
E . They have a gram molecular weight of more than 1.0 whereas Gram-negative bacteria have a gram molecular weight of less than 1.0

E. They have a gram molecular weight of more than 1.0 whereas Gram-negative bacteria have a gram molecular weight of less than 1.0

Flagella occur in both prokaryotes and eukaryotes. Which of the following statements DOES NOT describe how the flagella of prokaryotes and eukaryotes differ?

A.Eukaryotic flagella have microtubules in a cytoskeleton whereas prokaryotic ones do not.
B. Eukaryotic flagella have the motor protein dynein whereas the prokaryotic one does not.
C. The eukaryotic flagellum is covered by the plasma membrane whereas that of the prokaryotes is not.
D. Prokaryotic flagella have a basal apparatus and hook that rotates the filament whereas eukaryotic flagella do not.
E. The filament of eukaryotes is multilayered whereas that of prokaryotes is a single strand.

E. The filament of eukaryotes is multilayered whereas that of prokaryotes is a single str

Which of the following structures allow microbes to glide across surfaces?
A.flagella
B. gas vesicles
C. microtubules
D. filament
E. pili

E. pili

Binary fission is:
A.cell division by meiosis
B. cell division by mitosis
C. cell division by simple splitting
D. fluorescent in situ hybridization (FISH)
E. exchange of genes between two cells

C. cell division by simple splitting

The difference between an akinete and endospore is that:
A. Akinetes are whole cells filled with food, whereas endospores are bodies produced inside of cells.
B. Akinetes are not capable of locomotion whereas endospores move freely.
C. Akinetes cannot resist stressful conditions whereas endospores can.
D. Endospores cannot resist stressful conditions whereas akinetes can.
E. Akinetes are reproductive structures whereas endospores are dormant, resistant structures

A. Akinetes are whole cells filled with food, whereas endospores are bodies produced inside of cells.

Which of the following diseases is NOT caused by endospore-forming bacteria?
A.pneumonia
B. botulism
C. anthrax
D. tetanus
E. lockjaw

A.pneumonia

The oldest spores from which bacteria have been successfully cultured were:
A. ten weeks old
B. ten years old
C. 7,000 years old
D. 25 million years old
E. 250 million years old

E. 250 million years old

The process whereby genetic exchange occurs by way of viruses carrying genes from one microbe to another is known as:
A. conjugation
B. transduction
C. transformation
D. transubstantiation
E. interchange

B. transduction

What is the source of energy for a photoautotroph?
A.carbon dioxide
B. inorganic compounds
C. organic compounds
D. light
E. living hosts

D. light

The atmosphere and seas of the early Earth lacked oxygen. What kind of organisms could NOT have lived under those conditions?
A. obligate aerobes
B. obligate anaerobes
C. cyanobacteria
D. chemoautotrophs
E. All of the other choices are correct

A. obligate aerobes

A bacterial "bloom" is:

A. the reproductive parts of bacteria
B. malformation of flowers caused by bacterial infections
C. unusual coloring of the water of lakes, ponds, or the sea caused by high numbers of bacteria
D. souring of milk caused by bacteria
E. swelling of a wound because of bacterial infection

C. unusual coloring of the water of lakes, ponds, or the sea caused by high numbers of bacteria

Which of the following series is arranged in the correct sequence of occurrence during the fixation and subsequent use of nitrogen?

A. atmospheric nitrogen; bacterial nitrogenase; ammonia; conversion by plants or algae; synthesis of proteins
B. atmospheric nitrogen; bacterial nitrogenase; conversion by plants or algae; ammonia; synthesis of proteins
C. atmospheric nitrogen; ammonia; bacterial nitrogenase; conversion by plants or algae; synthesis of proteins
D. atmospheric nitrogen; ammonia; bacterial nitrogenase; synthesis of proteins; conversion by plants or algae
E. none of the other options displayed

A. atmospheric nitrogen; bacterial nitrogenase; ammonia; conversion by plants or algae; synthesis of proteins

Organisms that fix nitrogen are called:
A. fertilizers
B. nitrophiles
C. diazotrophs
D. nodules
E. none of the options listed

C. diazotrophs

Methanotrophs affect global temperature. This is because:

A. Methanotrophs use oxygen produced by plants to metabolize methane, thereby reducing the amount of methane in the atmosphere. Since methane is one of the greenhouse gases whose accumulation causes a rise in global temperature, its reduction by methanotrophs helps prevent global warming.
B. Methanotrophs convert methane to carbon dioxide and increase the amount of carbon dioxide in the atmosphere. Since carbon dioxide is one of the greenhouse gases whose accumulation causes a rise in global temperature, its production by methanotrophs contributes to global warming.
C. Methanotrophs convert carbon dioxide to methane and increase the amount of methane in the atmosphere. Since methane is one of the greenhouse gases whose accumulation causes a rise in global temperature, its production by methanotrophs contributes to global warming.
D. Methanotrophs convert methane to carbon dioxide, thereby decreasing the amount of methane in the environment but increasing the amount of carbon dioxide there. Since both methane and carbon dioxide are greenhouse gases whose accumulation causes a rise in global temperature, the decrease in one cancels the increase in the other and methanotrophs have no net effect on global warming.
E. Methanotrophs combine carbon dioxide and methane to form petroleum and in this way take both methane and carbon dioxide out of the atmosphere. Since both methane and carbon dioxide are greenhouse gases whose accumulation causes a rise in global temperature, the decrease in both helps prevent global warming.

A. Methanotrophs use oxygen produced by plants to metabolize methane, thereby reducing the amount of methane in the atmosphere. Since methane is one of the greenhouse gases whose accumulation causes a rise in global temperature, its reduction by methanotrophs helps prevent global warming.

A lichen is an example of:
A.a pathogen
B. a parasite
C. an archaean
D. a methanogen
E. a mutualistic relationship

E. a mutualistic relationship

Two kinds of organisms living together in ways beneficial to both is called:
A.mutualism
B. bonding
C. parasitism
D. sociality
E. none of the other choices provided

A.mutualism

A parasite is also a(n):

A.nitrogen fixer
B. autotroph
C. heterotroph
D. methanogen
E. mutualist

C. heterotroph

Bird influenza is an emerging disease. If you were given the task of using Koch's postulates of finding the pathogen causing bird flu, what sequence of procedures should you use?

A.(1) Inoculate a healthy bird with the suspected pathogen to see whether it becomes sick, (2) compare symptoms of that bird with those from a bird known to have the disease, (3) isolate the pathogen from both birds in pure culture and stain them to see whether they are both Gram-positive, and (4) make a vaccine from the pure culture of one bird and inject it into another to see if it recovers.
B. (1) Take blood samples from a sick bird, (2) isolate the pathogen in pure culture, (3) treat the bird for the disease and when it recovers take a second blood sample, and (4) test the blood to check whether it no longer contains the pathogen.
C. (1) Inject a bird with the suspected pathogen, (2) inject another bird with a control that doesn't contain the suspected pathogen, (3) repeat with more birds, and (4) plate out samples of blood from both kinds of birds to see if you can isolate the pathogen in pure culture.
D. (1) Isolate in pure culture the suspected pathogen from sick birds, then (2) use a series of medications to treat the sick birds, (2) select the medication that worked best, (3) apply that medication to pure cultures of the pathogen, and (4) see whether it kills the pathogen, compared to control treatments without the medication.
E. (1) Check whether the presence of the suspected pathogen correlates with the occurrence of symptoms, then (2) isolate the pathogen from an infected bird and grow it in pure culture, (3) inoculate cells from pure culture into a healthy host to see whether it causes the disease, and (4) attempt to isolate the suspected pathogen from the inoculated host.

E. (1) Check whether the presence of the suspected pathogen correlates with the occurrence of symptoms, then (2) isolate the pathogen from an infected bird and grow it in pure culture, (3) inoculate cells from pure culture into a healthy host to see whether it causes the disease, and (4) attempt to isolate the suspected pathogen from the inoculated host.

The secretory systems of Type III and Type IV pathogenic bacteria differ in their mode of attacking cells in which of the following ways?
A. Type III systems bind to the cellular membrane by slimy mucilage and toxins diffuse across the membrane, whereas Type IV systems infect materials using pili as transfer tubes.
B. Type IV systems bind to the cellular membrane by slimy mucilage and toxins diffuse across the membrane, whereas Type III systems infect materials using pili as transfer tubes.
C. Both systems attach to cells in the same way but they differ merely in the chemicals that they inject into the host cell.
D. Type III systems use flagella modified as "syringes" to inject materials into cells they are infecting whereas Type IV systems use modified pili as transfer tubes.
E. Type IV systems use flagella modified as "syringes" to inject materials into cells they are infecting whereas Type III systems use modified pili as transfer tubes

D. Type III systems use flagella modified as "syringes" to inject materials into cells they are infecting whereas Type IV systems use modified pili as transfer tubes.

Which of the following is NOT a way that bacteria benefit humans?
A. produce foodstuffs such as cheese
B. produce antibiotics
C. break down substances harmful to humans, such as wastes, toxins, explosives, and petrochemicals
D. kill harmful insects
E. transfer nutrients across intestinal membranes

E. transfer nutrients across intestinal membranes

Bioremediation is:
A.the use of microorganisms to treat open wounds
B. the use of microorganisms to break down harmful substances such as sewage, pesticides, petrochemicals, and explosives
C. the use of bacteria to attack cancer cells
D. the use of microorganisms to attack pathogenic bacteria
E. none of the other options presented

B. the use of microorganisms to break down harmful substances such as sewage, pesticides, petrochemicals, and explosives

Archaea, Bacteria, and Eukarya are:
A.phyla
B. kingdoms
C. families
D. domains
E. none of the options listed

D. domains

Plastids originated from which of the following groups of bacteria?
A. Cyanobacteria
B. Spirochaetes
C. Proteobacteria
D. Staphlococcus
E. Actinobacteria

A. Cyanobacteria

An obligate anaerobe is an organism that:

A. is poisoned by oxygen
B. requires oxygen
C. can use oxygen but can get along without it
D. produces oxygen
E. has none of the options listed

A. is poisoned by oxygen

The evolution of organisms that use oxygen in their respiration was possible only because of the action of a group of bacteria that produced oxygen and changed the Earth's atmosphere from an anoxic one to one rich in oxygen. That group of bacteria was:
A.Cyanobacteria
B. spirochaetes
C. Proteobacteria
D. Staphylococcus
E. Actinobacteria

A.Cyanobacteria

Some bacteria exhibit a primitive form of behavior in that they can sense the properties of their environments and use that ability to make adaptive responses. Which of the following are NOT capabilities of any known bacterium?
A. orientation with respect to the Earth's magnetic field
B. move to other bacteria and aggregate with them in response to chemical signals
C. find nutrients by moving upward in the water column with the aid of flotation devices
D. respond to other individual bacteria and transmit DNA via conjugation
E. none of the other options presented

E. none of the other options presented

The Danish physician Hans Christian Gram
A. developed the Gram-stain technique
B. devised the metric system of weights (milligrams, grams, kilograms)
C. developed the procedures for determining whether a particular organism causes a specific disease
D. developed both the Gram stain and the method of determining whether a particular organism causes a specific disease
E. none of the other options presented

A. developed the Gram-stain technique

Many new, previously unsuspected species have been discovered through application of the molecular technique of DNA sequencing.

TRUE

Archaea that tolerate and/or require high salinities are called halophiles.

TRUE

Heterocysts are specialized cells in plant roots that contain nitrogen-fixing bacteria.

TRUE

Various anaerobic Archaea that convert carbon dioxide and other carbon-bearing compounds into methane are called methanotrophs.

FALSE

Type III and Type IV systems are potentially applicable to treatment of human disease by using them to deliver DNA to target cells in human gene therapy

TRUE

Most microbes that are extremophiles are Archaea.

TRUE

Archaea are prokaryotes and Bacteria are eukaryotes.

FALSE

A pathogen is a parasitic microbe

TRUE

Feeding antibiotics to livestock promotes human health.

FALSE

Mitochondria originated from Proteobacteria

TRUE