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The cells wall of bacteria Z contains high concentrations of phospholipids along with proteins and relatively low amounts of lipopolysaccharide.When bacteria Z is gram stained, it will most like be colored?


A) Purple
B) Pink
C) Blue
D) Clear, it does not retain any stain

E) All of the above
F) B) and C)

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Prokaryotic cell walls consist of a network of polysaccharide molecules connected by cross-bridges of


A) other polysaccharides.
B) lipids.
C) peptides.
D) ribosomes.

E) B) and D)
F) B) and C)

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Irregular dental hygiene and a high sugar diet may led to tooth decay.Why?


A) Bacteria consume calcium.
B) Lactic acid fermentation is used to generate ATP under anaerobic conditions.
C) Plaque degrades the tooth's protective mucosal layers.
D) Glucose forms a weak acid when dissolved in saliva.

E) A) and D)
F) B) and C)

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A microbiologist is conducting a research project on chemolithoautotrophs.This means that the investigator is examining certain aspects of a bacterium that


A) can oxidize inorganic molecules such as ammonia and sulfur for energy
B) is a purple non-sulfur bacteria which depends on light.
C) obtains carbon from organic molecules.
D) can use the energy from sunlight to build organic molecules from carbon dioxide.

E) C) and D)
F) B) and D)

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Bacterial ribosomes differ from eukaryotic ribosomes in all of the following except


A) they act as sites of protein synthesis.
B) they are smaller than in eukaryotes.
C) tetracycline and chloramphenicol can bind to bacterial ribosomes.
D) they differ in ribosomal proteins.

E) A) and D)
F) All of the above

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Genes abc and def have a high average cotransduction frequency.Genes abc and xyz have a very low average cotransduction frequency.What is the best explanation for this difference?


A) The genes abc and def are much closer to each other on the chromosome.
B) The genes abc and def must share a higher degree of sequence similarity.
C) Both genes have a high affinity for the viral binding sites.
D) Both genes code for gene products that are necessary for viral replication.

E) B) and C)
F) A) and B)

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Various techniques have been developed to isolate strains of bacteria carrying a particular mutation.One of them is, bacteria containing wild-type cells and cells of a desired mutant are grown on a medium lacking the nutrient for which the desired mutants are auxotrophic but containing an antibiotic that only kills growing cells.In this environment,


A) both wild-type and mutant cells are killed.
B) both wild-type and mutant cells survive.
C) wild-type cells survive; mutant cells die.
D) wild-type cells die; mutant cells survive.

E) B) and D)
F) A) and D)

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Genetic diversity in bacteria is created by mutation and __________.

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A high concentration of chlorophyll imbedded in the plasma membrane fold of a newly discovered species of bacteria suggests a:


A) Chemolithoautotrophic metabolism
B) Chemoheterotrophic metabolism
C) Photoautotrophic metabolism
D) Photoheterotrophic metabolism

E) C) and D)
F) A) and C)

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The fungus Penicillium produces a compound that blocks peptidoglycan assembly.Why is a fungus trying to kill bacteria?


A) Fungi eat bacteria.
B) Fungi and bacteria are both decomposers and compete for resources.
C) The compound produced by the fungus is used for nitrogen fixation, the antibacterial properties are accidental.
D) The fungal compound is produced in response to a bacterial invasion of the fungal hyphae.

E) A) and B)
F) B) and C)

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Dental plaque (a biofilm) , a first stage in tooth decay, consists of


A) sugars.
B) bacteria surrounded by a polysaccharide matrix.
C) fluoride.
D) lactic acid.

E) A) and B)
F) None of the above

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In all of the following characteristics, prokaryotes differ from eukaryotes except in


A) cell size.
B) multicellularity.
C) chromosomes.
D) nucleic acids as the hereditary material.

E) All of the above
F) B) and D)

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Which of the following statements about tuberculosis (TB) is false?


A) MDR TB is more expensive to treat.
B) Not completing a full course of antibiotic can select for MDR strains.
C) HIV and TB can be transmitted in the same manner.
D) The spread of TB can be very rapid.

E) All of the above
F) B) and D)

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Prokaryotes reproduce rapidly and this allows genetic variation to spread quickly through a population.Two processes can create new variations in prokaryotic populations.Select the choice with those two processes.


A) mutation and phage viral attack
B) phage viral attack and genetic recombination
C) genetic recombination and nondisjunction
D) genetic recombination and mutation

E) None of the above
F) A) and C)

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Gonorrhea and syphilis are most commonly controlled by


A) abstinence.
B) antibiotics.
C) boiling water.
D) fluoride treatment.

E) A) and B)
F) A) and C)

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Which of the following statements about generalized transduction is false?


A) "Head full" packaging always places only phage DNA into the phage head during phage packaging in generalized transduction.
B) Generalized transduction always involves lytic phage.
C) Generalized transduction can be used to map bacterial genes.
D) Genes that are close together on the bacterial chromosome will have a relatively large cotransduction frequency.

E) A) and C)
F) B) and D)

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When bacteria are exposed to nutrient-poor conditions, they form thick-walled structures that contain the chromosome and a small amount of cytoplasm.These structures are called


A) plasmids.
B) pseudomonads.
C) nucleoids.
D) endospores.

E) C) and D)
F) B) and C)

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Current classification of prokaryotes is based on


A) morphology of flagella.
B) sequencing of proteins, DNA, and RNA.
C) occurrence of transverse binary fission.
D) type of colony formation.

E) A) and B)
F) A) and C)

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The prokaryotic DNA is located in the


A) capsid region.
B) nucleoid region.
C) endospore region.
D) peptidoglycan region.

E) All of the above
F) B) and C)

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In some bacteria, a capsule surrounds the cell wall.It is made up of


A) a lipopolysaccharide.
B) peptidoglycan.
C) gelatin.
D) pili.

E) A) and D)
F) B) and D)

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