Deck 27: Prokaryotes

Question 1

Early classification systems of the bacteria employed all of the following characteristics except

A)the ability to photosynthesize.
B)rRNA sequences.
C)motility.
D)colony or filament forming.
E)sporulation or binary fission.

Answer 1

B

Question 2

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.

Answer 2

B

Question 3

If the label on a slide reads Gram-positive bacillus,what would a students expect to see?

A)Pink helical cells
B)Purple rod shaped cells
C)Red spherical cells
D)Blue coiled cells

Answer 3

B

Question 4

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

Question 5

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.

Question 6

Many cells of the immune system have receptors that detect peptidoglycans and lipopolysaccharides.How do pathogenic bacteria avoid detection?

A)Pathogenic bacteria lack cell walls.
B)Pathogens often encase themselves in a gelatinous capsule.
C)Peptidoglycans are absent from pathogenic bacteria.
D)Disease is only possible if the immune system has been compromised by some other event.

Question 7

Phil has chronic ulcers,he has been taking acid blockers and drinking vast amounts of liquid antacids.These help relieve the symptoms but he still suffers from ulcers.What would be the best course of action to treat the source of his ulcers?

A)Taking several different antacids
B)Increasing the dosage of acid blockers
C)Taking a course of antibiotics
D)Reducing the stress in his daily life
E)Changing his diet to include more fiber

Question 8

Vibrio cholerae produces a toxin that destroys the intestinal epithelium.This leads to massive diarrhea; the diarrhea can kill the human via dehydration but helps the bacteria spread and colonize other humans.What is this relationship?

A)Mutualistic
B)Commensalistic
C)Symbiotic
D)Atavistic

Question 9

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)High concentrations of sugar soften the tooth enamel.

Question 10

Amanda is a microbiologist who studies the pathogenic bacteria Streptococcus pyogenes.In what ways are they (Amanda and the bacteria)similar?

A)Both have cell walls.
B)Both have linear chromosomes.
C)Both have mitochondria for ATP production.
D)Both are capable of sexual reproduction.
E)Both obtain carbon from consuming organic molecules.

Question 11

Bacteria typically use binary fission,but under special circumstances sexual reproduction is possible via horizontal gene transfer.

Question 12

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)ability to stain the cell wall with Gram stain.

Question 13

A researcher observed a reduction in the number of chromosomes during cell division for a microbe,he concludes that the microbe must be

A)Eukaryotic
B)Prokaryotic
C)An archaean
D)a virus

Question 14

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

Question 15

An oil spill occurs,and Greg (a member of the clean up team)suggests adding fertilizer.Why is he making this suggestion?

A)The fertilizer encourages the growth of microbes that can break down the oil.
B)The chemicals in the fertilizer digest the oil residues.
C)The fertilizer interacts with the oil droplets and renders them harmless.
D)The fertilizer volitizes the oil.

Question 16

Why is chlamydia much more common than syphilis?

A)Chlamydia is spread via droplet inhalation.
B)Syphilis can penetrate a condom whereas chlamydia cannot.
C)Many chlamydia infections are asymptomatic.
D)Chlamydia is viral,and viral diseases spread much quicker.
E)Chlamydia is resistant to most antibiotics.

Question 17

Are transformation and transduction the same process?

A)Yes; they both involve the acquisition of viral genes.
B)No; only transformation passes on genes for pathogenicity.
C)Yes; both processes transfer specific gene products to a specific bacterium.
D)No; although both involve gene transfer the sources of the genetic material differ.

Question 18

Why are children often told that if they eat too much candy their teeth will fall out?

A)Sugar attacks tooth enamel.
B)Sugars gradually replace the tooth enamel.
C)Bacteria use the sugar to make ATP.This fermentation process produces acids as a by-product.
D)Bacteria secrete acids in order to digest the sugar molecules.

Question 19

Farmers often practice crop rotation to help enrich agricultural fields.Why are beans and other legumes often used in the rotations?

A)Beans fix nitrogen.
B)Bacteria in legume root nodules are nitrifiers.
C)Legumes enrich the soil by forming heterocysts.
D)Legumes remove toxins from the soil.
E)Less carbon dioxide.

Question 20

DNA replication and gene expression in archaeans more closely resemble eukaryotic cells than the same processes in bacteria.However both Bacteria and Archaea are prokaryotic.What does this suggest?

A)Eukaryotic cells are descended from modern Archaeans.
B)Bacterial cells are not related to Archaeans.
C)Eukaryotic cells shared a more recent common ancestor with Archaeans than with bacterial cells.
D)There must have been 2 origin events,one producing the bacteria and the other producing Archaeans and eukaryotic cells.

Question 21

Prokaryotes are very important ecologically because of their involvement in all of the following except

A)photosynthesis.
B)nitrogen fixation.
C)STDs.
D)denitrification.
E)bioremediation.

Question 22

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)organelles.

Question 23

A microbiologist suspects a strain of Staphylococcus aureus is resistant to methicillin.What would be the best approach to test this suspicion?

A)Perform a Gram stain.
B)Sequence the chromosome looking for resistance genes.
C)Calculate the doubling time for the bacteria.
D)Inject the bacteria into a host animal and look for disease symptoms.
E)Add methicillin to the growth plates.

Question 24

Prokaryotes that harvest both energy and carbon atoms from organic molecules are called

A)photoautotrophs.
B)chemolithoautotrophs.
C)photoheterotrophs.
D)chemoheterotrophs.
E)nitrogen fixers.

Question 25

Some prokaryotes attach to other substrates by hairlike outgrowths,which are shorter than flagella.These are called

A)endospores.
B)flagellin.
C)pili.
D)plasmids.
E)fission products.

Question 26

Prokaryotes split into two lines early in the history of life.The differences are so fundamental that they are assigned to two different domains,the ________ and the Bacteria.

Question 27

Archaea differ from Bacteria in all of the following EXCEPT

A)cell wall composition.
B)plasma membrane make up.
C)DNA replication.
D)gene expression.
E)the presence of a nucleoid region.

Question 28

Carbon fixation carried out by the prokaryotes known as the ________ involves chlorophyll a.

Question 29

Bacteria cause all of the following human diseases except

A)cholera.
B)diphtheria.
C)tuberculosis.
D)tetanus.
E)malaria.

Question 30

Members of the genus ________ are associated with scarlet fever,rheumatic fever,pneumonia,etc.

Question 31

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)exospores.

Question 32

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)chromosomal DNA.

Question 33

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

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

Question 34

The prokaryotic DNA is located in the

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

Question 35

Cell walls of bacteria (domain Bacteria)usually consist of ________,a network of polysaccharide molecules connected by polypeptide cross-links.

Question 36

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)they differ in RNA content.

Question 37

Which of the following is not a shape seen in prokaryotes?

A)Spheres
B)Rods
C)Spirals
D)Icosahedrals

Question 38

Certain prokaryotes can withstand drying and hotter temperatures because of their ability to form

A)cell walls.
B)endospores.
C)flagella.
D)organelles.
E)plasmids.

Question 39

Genetic diversity in bacteria is created by mutation and ________.

Question 40

Prokaryotes undergo a process that produces cells that are identical.This process is called

A)mitosis.
B)meiosis.
C)conjugation.
D)binary fission.
E)syngamy.

Question 41

If left untreated,syphilis infections go through four stages.The first stage is a sore called a chancre.The signs of the second stage are

A)some nerve damage,loss of some teeth,and perhaps a dimming of color vision.
B)very few,with many victims having no symptoms.
C)rash,sore throat,and sores in the mouth
D)persistence of the chancre and bleeding at the chancre site.
E)a yellowish-white discharge from the urethra.

Question 42

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)genetic recombination and rapid cell division

Question 43

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 nonsulfur 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)uses light as its energy source and carbon for organic compounds.

Question 44

Plasmids are distinguished from bacterial chromosomes in that

A)plasmids are circular,bacterial chromosomes are linear.
B)plasmids occur in the cytoplasm,bacterial chromosomes occur in the nucleus.
C)plasmids are composed of RNA,bacterial chromosomes are composed of DNA.
D)plasmids have few genes,bacterial chromosomes have many genes.
E)plasmids consist of single-stranded nucleic acids,bacterial chromosomes consist of double-stranded nucleic acids.

Question 45

Which of the following statements about sexually transmitted diseases (STDs)is false?

A)Gonorrhea,syphilis,and chlamydia are all transmitted through sexual contact.
B)Because chlamydia has both bacterial and viral characteristics,it cannot be treated with antibiotics.
C)Chlamydia is known as the "silent STD."
D)The incidence of chlamydia has increased as gonorrhea has decreased.
E)Syphilis can be transmitted from a mother to her fetus.

Question 46

The data below shows recombination of genes (1-5)according to the amount of time available for transfer of the bacterial chromosome during conjugation between different genetic strains in E coli.Based on these data,which gene is closest to gene 1? (Note: The entire chromosome is transferred in 100 minutes.)

A)gene 2
B)gene 3
C)gene 4
D)gene 5

Question 47

A bacterium is found that can photosynthesize in the presence of light but uses hydrogen sulfide and releases elemental sulfur as a by-product.This organism can best be classified as a

A)chemolithoautotroph.
B)chemoheterotroph.
C)photoautotroph.
D)photoheterotroph.
E)pathogen.

Question 48

Gonorrhea and syphilis are most commonly controlled by

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

Question 49

Tuberculosis remains a serious worldwide health problem due to all of the following except

A)multi-drug resistance.
B)social factors such as crowding and incarceration.
C)the prevalence of HIV infections.
D)ease of transmission.
E)absence of MDR strains.

Question 50

Which of the following statements about transformation is false?

A)The bacterium E.coli is incapable of natural transformation.
B)Like transduction and conjugation,natural transformation is an "accident" of plasmid biology.
C)Artificial transformation is essential to many recombinant DNA techniques.
D)All R-plasmids contain antibiotic-resistance genes.
E)Natural transformation of the Enterobacteriaceae is a significant public health risk.

Question 51

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)only double mutants survive.

Question 52

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)The reservoir of TB is humans and no vector is required for transmission.

Question 53

You expose a tube of bacteria to ultraviolet radiation to induce mutations.You then spread the bacteria on a plate containing media with all known required nutrients and wait until separate colonies form.Finally,you use replicate plating to transfer a print of this plate to an additional sterile plate containing minimal media plus a known required nutrient for the bacteria.Based on this protocol,colonies growing on the plate with minimal media would include what type of cells?

A)only wild-type bacteria
B)only mutant bacteria
C)mutants that only require the supplied nutrient
D)Both wild-type and all mutants
E)wild-type bacteria and the mutants that only require the supplied nutrient

Question 54

The enzymes for cellular respiration in eukaryotic organisms are located within the mitochondria.In prokaryotic organisms,these enzymes are attached to the

A)cell wall.
B)cell membrane.
C)ribosomes.
D)circular DNA.
E)nuclear membrane.

Question 55

Bacterial sexually transmitted diseases include all of the following except

A)gonorrhea.
B)syphilis.
C)chlamydia.
D)herpes.

Question 56

A microbiologist explains to one of her biology classes that her research focuses on the nucleoid region of the cholera bacteria.This means that she is studying a region within the bacterium that contains the

A)nucleic acids.
B)nuclear membrane.
C)R plasmids.
D)peptidoglycan.

Question 57

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)Two recombination events are necessary to integrate the transferred DNA during generalized transduction.

Question 58

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)bacteria and high pH.

Question 59

Which of the following statements about Hfr cells and bacterial conjugation is false?

A)An Hfr cell becomes an F^- cell if its integrated F plasmid is excised.
B)If excision of the F plasmid from an Hfr cell includes some bacterial genes,a partial diploid can result.
C)The genes that are transferred from an Hfr cell into a recipient cell during conjugation replace the equivalent genes in the recipient cell.
D)An F' plasmid contains some bacterial genes.
E)Cells with integrated F' plasmid have two copies of some genes.

Question 60

Which of the following events is least likely to result in a genetic change in a bacterium?

A)pilus formation
B)conjugation
C)specialized transduction
D)generalized transduction
E)natural transformation

Question 61

Check all of the mutually beneficial relationships between prokaryotes and eukaryotes.

A)Prokaryotes aid in digestion in ruminants.
B)The human microbiome aids in human health.
C)Nitrogen-fixing bacteria live in plant root nodules.
D)Agrobacterium tumefaciens bacteria that form galls in some plants.