Jo O'Bar
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Study guide for Microbiology I at UWF. Questions are taken directly from the sample exam

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Microbiology Exam 2

Pregunta 1 de 81

1

Which is true about biological reduction of nitrogen gas to ammonia?

Selecciona una de las siguientes respuestas posibles:

  • Can be accomplished by free-living organisms in Domains Archaea and Bacteria

  • Can be accomplished by a variety of symbioses between prokaryotes and eukaryotic macro organisms

  • Is thermodynamically exergonic but requires high input of cellular energy (ATP)

  • Is catalyzed by an enzyme that typically contains iron and molybdenum co-factors

  • All of these answers are true

Explicación

Pregunta 2 de 81

1

The tendency of systems to go from a lower state of order to a more organized system is supported by which of the below?

Selecciona una de las siguientes respuestas posibles:

  • entropy

  • First Law of Thermodynamics

  • Second Law of Thermodynamics

  • Chemiosmotic Theory

  • None of these answers are correct

Explicación

Pregunta 3 de 81

1

Enzyme(s) by which bacteria assimilate gaseous molecular nitrogen is/are...

Selecciona una de las siguientes respuestas posibles:

  • Nitrogenase

  • Glutamine synthetase (GS)

  • Glutamate synthase (GOGAT)

  • Glutamate degydrogenas (GDH)

  • Both Nitrogenase and GS

Explicación

Pregunta 4 de 81

1

The Ames test...

Selecciona una o más de las siguientes respuestas posibles:

  • determines histidine resistace of Salmonella typhimurium

  • uses Salmonella typhimurium

  • depends on reversion of histidine auxotrophs to prototrophy

  • assesses chemical mutagenicity

Explicación

Pregunta 5 de 81

1

Bacterial cells are not diploid because...

Selecciona una de las siguientes respuestas posibles:

  • they do not reproduce sexually

  • their DNA is single-stranded

  • their DNA is double-stranded

  • they use plasmids to reproduce

  • they usually have only one set of chromosomes

Explicación

Pregunta 6 de 81

1

Strains of E. coli with an F-factor that has integrated into the chromosome are known as

Selecciona una de las siguientes respuestas posibles:

  • Hfr strians

  • Super males

  • F+ strains

  • Episomes

  • All of these answers are correct

Explicación

Pregunta 7 de 81

1

Which of these mechanism(s) do NOT protect nitrogenase from denaturation by molecular oxygen?

Selecciona una de las siguientes respuestas posibles:

  • fixation of nitrogen under aerobic conditions

  • heterocysts of cyanobacteria that separate nitrogen fixation from oxygenic photosynthesis

  • uncoupling of oxidation from phosphorylation in respiratory chain (electron transport system)

  • leghemoglobin

  • all of these answers are correct

Explicación

Pregunta 8 de 81

1

Housekeeping genes are

Selecciona una de las siguientes respuestas posibles:

  • constitutively expressed

  • essential to growth and life of the cell

  • useful to determine whether a cell is active even without culturing it

  • all of these answers are correct

  • none of these answers are correct

Explicación

Pregunta 9 de 81

1

Which of the below contributed most to our understanding of "sex" in bacteria?

Selecciona una de las siguientes respuestas posibles:

  • Joshua Lederberg and Edward Tatum

  • Paul Berg

  • Myron Sasser

  • Max Delbruck and Salvador Luria

  • The Kardashians

Explicación

Pregunta 10 de 81

1

Transfer of gnetic information between prokaryotes that requires direct physical contact between the donor and recipient cells and does NOT require a bacterial virus is called

Selecciona una de las siguientes respuestas posibles:

  • transformation

  • transduction

  • Transcendental Mediation

  • conjugation

  • none of these answers are correct

Explicación

Pregunta 11 de 81

1

Four- and five-carbon sugars and NADPH, essential for biosynthetic (anabolic) functions, are provided by which pathway?

Selecciona una de las siguientes respuestas posibles:

  • oxidatie pentose phosphate

  • Entner-Doudoroff

  • Tricarboxylic acid cycle

  • Glycolysis

  • Embden-Meyerhof, Parnas

Explicación

Pregunta 12 de 81

1

Regulation of metabolic pathways within microorganisms is controlled in which of the following ways?

Selecciona una de las siguientes respuestas posibles:

  • altering activity of key enzymes

  • regulating biosyntheseis--and thus the amount--of key enzymes

  • induction and regression of genes

  • feedback inhibition of key enzymes by end products of a pathway

  • all of the above

Explicación

Pregunta 13 de 81

1

Why did Lederberg and Tatum use multiple auxotrophic mutants, i.e., strains with deficiencies in biosynthetic capabilities in several places, in their experiment that demonstrated conjugation in bacteria?

Selecciona una de las siguientes respuestas posibles:

  • Each mutation has reversion rate 10*-8 per cell per generation. Thus, 10 in a billion cells will revert to wild-type. By using 3 mutants, the likelihood of all three reverting to wild type is infinitesimally small

  • They had a lot of auxotrophs in their culture collection

  • To prove the Mobilome

  • They were sex addicts

  • none of these answers are correct

Explicación

Pregunta 14 de 81

1

Positive control of gene transcription involves

Selecciona una de las siguientes respuestas posibles:

  • a regulator protein binding to the DNA operon.

  • interaction of a regulator protein with DNA that is not a cestron

  • enhancement of transcription effieceny

  • suppression of trascription efficiency

  • All except D

Explicación

Pregunta 15 de 81

1

Positive control of gene transcription involves

Selecciona una o más de las siguientes respuestas posibles:

  • A regulator protein binding to the DNA operon

  • interaction of a regulator protein with DNA that is not a cistron

  • enhancement of transcription efficiency

  • suppression of trascription efficiency

Explicación

Pregunta 16 de 81

1

Specific regulatory interaction between proteins and DNA

Selecciona una de las siguientes respuestas posibles:

  • is common and occurs in all domains in life

  • is restricted to only Domain Bacteria

  • is restricted to only Domain Eukarya

  • is restricted to only Domain Archaea

  • is restricted to only the prokaryotic domains of Bacteria and Archaea

Explicación

Pregunta 17 de 81

1

Genomes of Domain Bacteria...

Selecciona una o más de las siguientes respuestas posibles:

  • are haploid.

  • typically consist of one chromosome.

  • are covalently closed circular DNA.

  • may be composed of single-stranded DNA.

Explicación

Pregunta 18 de 81

1

Nonsense-supressor mutations...

Selecciona una de las siguientes respuestas posibles:

  • allow a translation stop codon to be ignored.

  • require a change in tRNA specificity

  • restore in the original, wild phenotype

  • result in substitution of an amino acid into the position specified by the stop codon in the mRNA

  • All of these answers are correct

Explicación

Pregunta 19 de 81

1

Plasmid copy number is which of the below?

Selecciona una de las siguientes respuestas posibles:

  • The same as chromosomal copy number.

  • The ratio between the numbers of a specific plasmid inside a bacterial cell and the number of chromosomes.

  • The total copies of a plasmid in a single cell.

  • How efficiently a plasmid is copied during cell division.

  • The number of genes carried on each plasmid

Explicación

Pregunta 20 de 81

1

Nitrogenase...

Selecciona una o más de las siguientes respuestas posibles:

  • is an enzyme

  • is common in Domain Eukarya

  • may catalyze reduction of substrates other than nitrogen gas

  • is highly conserved in Domains Bacteria and Archaea

Explicación

Pregunta 21 de 81

1

The use of terminal electron acceptors other than molecular oxygen at the end of an electron transport chain is...

Selecciona una o más de las siguientes respuestas posibles:

  • anaerobic respiration

  • common in heterotrophic macroorganisms including humans

  • assiilatory nitrate reduction

  • aerobic respiration

Explicación

Pregunta 22 de 81

1

Which bacteriophage is the model for specialized transduction?

Selecciona una de las siguientes respuestas posibles:

  • Coliphage Lambda (a phage that attacks E. coli)

  • coliphage 42

  • T-even coliphage

  • General transducing phages

  • None of these answers are correct

Explicación

Pregunta 23 de 81

1

The rolling circle mechanism of DNA replication is utilized...

Selecciona una o más de las siguientes respuestas posibles:

  • during conjugative trasfer of DNA into an F- recipient

  • during replication of DNA of some viruses

  • during most replication of bacterial chromosomes

  • by Eukarya

Explicación

Pregunta 24 de 81

1

What principal metabolic advantage does fermentation confer to the cell?

Selecciona una de las siguientes respuestas posibles:

  • Produces useful metabolic byproducts such as ethanol, acetone, lactic acid

  • Generates a prodigious quantity of ATP

  • oxidizes reduced electron carriers such as NADH

  • makes alcoholic beverages and cheeses that make people happy

  • All of these answers are correct

Explicación

Pregunta 25 de 81

1

Which of the below mapping methods will give information on the polar relationship of two genes, e.g., whether gene B is between genes A and C?

Selecciona una de las siguientes respuestas posibles:

  • co-transformation

  • co-trasduction

  • interrupted conjugation

  • sequencing of DNA bases

  • All of these answers are correct

Explicación

Pregunta 26 de 81

1

The uncoupling of oxidation from phosphorylation during trasport of electrons via an electron trasport system to a terminal electron acceptor

Selecciona una de las siguientes respuestas posibles:

  • occurs in some natural systems

  • can be experimentally induced with certain chemicals

  • results in generation of no ATP

  • produces heat

  • all of these answers are correct

Explicación

Pregunta 27 de 81

1

The capability of a bacterial strain or species to take up naked DNA is called

Selecciona una de las siguientes respuestas posibles:

  • competence

  • fertility

  • promiscuity

  • trasduction

  • lysogeny

Explicación

Pregunta 28 de 81

1

Which possible fates for DNA that has been introduced (exogenote) into a new host cell result in the MOST-stable transfer into future generations of the recipient cell?

Selecciona una de las siguientes respuestas posibles:

  • Recombination with the endogenote

  • Digestion catalyzed by host enzymes

  • Formation of a partial diploid cell

  • Formation of partial diploid clone

  • All of these answers are correct

Explicación

Pregunta 29 de 81

1

The most abundant single protein in the biosphere is

Selecciona una o más de las siguientes respuestas posibles:

  • a key enzyme of the Calvin-Benson-Bassham cycle

  • RuBisCO

  • pyruvate dehydrogenase

  • nitrogenase

Explicación

Pregunta 30 de 81

1

Okasaki fragments

Selecciona una de las siguientes respuestas posibles:

  • are proteins

  • encode housekeeping functions for the cell

  • are delicious but expensive appetizers at Japenese restaurants

  • accommodate the fact that DNA polymerase must synthesize the complementary new strand

Explicación

Pregunta 31 de 81

1

A metabolic pathway that fixes carbon dioxide into an organic molecule but does not support autotrophic growth is

Selecciona una de las siguientes respuestas posibles:

  • the reductive pentose phosphate cycle

  • an anaplerotic reaction

  • the reverse tricarboxylic acid cycle

  • the acetyl-CoA pathway

  • all of these answers are correct

Explicación

Pregunta 32 de 81

1

Who was curator for the genetic map of Escherichia coli for many years?

Selecciona una de las siguientes respuestas posibles:

  • Martha Hershey and Alred Chase

  • Avery, ClLeod and McCarty

  • Barbara Bachman

  • Barbara McClintock

  • Britney Spears

Explicación

Pregunta 33 de 81

1

For this course, we have adopted which terminology as our definition of a "gene?"

Selecciona una o más de las siguientes respuestas posibles:

  • DNA polynucleotide sequence that codes for a gene product, e.g., protein, tRNA, rRNA

  • Cistron

  • any DNA in a bacterial chromosome or plasmid

  • a DNA sequence with a specific start and end

Explicación

Pregunta 34 de 81

1

Which of the below used radioisotopes to demonstrate that the DNA and not the protein components of bacteriophages directed infection of the host cell?

Selecciona una de las siguientes respuestas posibles:

  • Avery, MacLeod, and McCarty

  • Hershey and Chase

  • Griffith

  • Watson and Crick

  • Gilbert and Sanger

Explicación

Pregunta 35 de 81

1

Auxotrophic mutant bacteria

Selecciona una de las siguientes respuestas posibles:

  • have the biosynthetic capability of the "wild type" e.g. typical bacteria of that species

  • may undergo reversion to their prototrophic forms

  • are resistant to multiple antibiotics

  • are able to obtain all their caron requirement by fixing carbon dioxide

Explicación

Pregunta 36 de 81

1

Which pathway of glucose catabolism is found only in prokaryotic microorganisms

Selecciona una de las siguientes respuestas posibles:

  • Entner-Doudoroff

  • Embden-Myerhof-Parnas

  • Calvin cycle

  • Oxidative Pentose Phosphate

  • Nitrogen fixation

Explicación

Pregunta 37 de 81

1

Who of belaw developed a "chemiosmotic" theory that provided a unified mechanism for how ATP was made during respiration and in the light reactions of photosynthesis?

Selecciona una de las siguientes respuestas posibles:

  • Peter Mitchell

  • Louis Pasteur

  • Woese, Falkow, Berg

  • Singer, Nicholson

  • Embden, Meyerhof, Parnas

Explicación

Pregunta 38 de 81

1

Small Interfering, siRNA, or "Silencer RNA" is used to

Selecciona una de las siguientes respuestas posibles:

  • suppress antibiotic resistant mutants

  • suppress expression of specific genes

  • select auxotrophic mutants

  • override stop codons

  • provide a mechanism for site-specific mutagenesis

Explicación

Pregunta 39 de 81

1

Who won the Nobel for discovering transposons

Selecciona una de las siguientes respuestas posibles:

  • Barbara McClintock

  • Barbara Bachman

  • Martha Hershey and Alfred Chase

  • Avery, McLeod and McCarty

  • Batman and Robin

Explicación

Pregunta 40 de 81

1

Which group below has a specialized cell that compartmentalizes nitrogen fixation and sequesters it from oxygenic photosynthesis

Selecciona una de las siguientes respuestas posibles:

  • filimentous cyanobacteria

  • purple non-sulfer bacteria

  • single-celled cyanobacteria

  • green sulfur bacteria

  • purple sulfur bacteria

Explicación

Pregunta 41 de 81

1

The principle that spontaneous mutations in bacteria are rare and random

Selecciona una de las siguientes respuestas posibles:

  • was supported by a fluctuation analysis experiment

  • was demonstrated by Max Delbruck and Salvador Luria

  • was demonstrated by using Poisson Distribution

  • was supported by following acquistition of mutant characteristics during the growth of E. coli in the absence of selection pressures

  • All of these answers are correct

Explicación

Pregunta 42 de 81

1

Selecciona la opción correcta del menú desplegable para completar el texto.

Under optimal conditions, the complete transfer of the entire chromosome during an Hfr x F- mating between two strains of E. coli takes approximately ( 100, 10, 200, 50, 20 ) minutes.

Explicación

Pregunta 43 de 81

1

Mutants of bacteria that are defectiv in biosynthetic capability relative to the wild type can be selected using which of the below?

Selecciona una de las siguientes respuestas posibles:

  • The Ames test

  • The auxotrophic-mutant rejection protocol

  • The Heimlich Maneuver

  • Use of penicillin counter-selection against prototrophs

  • Replica plating

Explicación

Pregunta 44 de 81

1

Which of the below are/were major player(s) in our understanding of biological nitrogen fixation?

Selecciona una de las siguientes respuestas posibles:

  • Robert Burris

  • Harold Evans

  • Arto Virtannen

  • Carnahan and ortenson

  • All of these answers are correct

Explicación

Pregunta 45 de 81

1

Which of the below discovered and experimentally demonstrated that a non-living "transforming" material could change an avirulent strain of a bacterium into a virulent, pathogenic microorganism?

Selecciona una de las siguientes respuestas posibles:

  • Avery, MacLeod, and McCarty

  • Fred Griffith

  • Hershey and Chase

  • Watson and Crick

  • Gilbert and Sanger

Explicación

Pregunta 46 de 81

1

Sulfanilamide...

Selecciona una o más de las siguientes respuestas posibles:

  • is a chemotherapeutic agent

  • competes with PABA (para-aminobenzoic acid) for an active site of an enzyme

  • is an antibiotic

  • stops transcription in bacteria

Explicación

Pregunta 47 de 81

1

To what does the term "bacteroid" refer?

Selecciona una de las siguientes respuestas posibles:

  • bacterial cells within genera Rhizobium or Bradyrhizobium that are symbiotic with leguminous plants

  • a prokaryote with characteristics similar to both Bacteria and Archaea

  • a prokaryotic bacterial cell with characteristics similar to those of eukaryotic cells

  • prokaryotic symbionts that a bacterium-like bacterium found on planets other than Earth

Explicación

Pregunta 48 de 81

1

How do bacteroids differ from the free-living bacteria?

Selecciona una de las siguientes respuestas posibles:

  • They are symbiotic form of genera Rhizobium or Bradyrhizobium with luminous plants

  • They cooperate with a plant host in producing legheoglobin

  • They reduce diatomic nitrogen gas to ammonia

  • All of these answers are correct

  • None of these answers are correct

Explicación

Pregunta 49 de 81

1

A bacterium experienceing a severe amino acid shortage

Selecciona una de las siguientes respuestas posibles:

  • may exhibit Stringent Response

  • will contain elevated levels of ppGpp

  • will continue biosynthesis of amino acids

  • will have a high level of uncharged tRNA

  • will have all of the listed properties

Explicación

Pregunta 50 de 81

1

Which pathway produces the most ATP?

Selecciona una de las siguientes respuestas posibles:

  • Entner-Doudoroff

  • Embden-Meyerhof-Pamas

  • Tricarboxylic acid cycle

  • Oxidative Pentose Phosphate Pathway

  • Electron transport chains coupled to chemiosmosis

Explicación

Pregunta 51 de 81

1

Who wrote a treatise on the "mobilome"--emphasizing horizontal gene transfer in bacteria

Selecciona una de las siguientes respuestas posibles:

  • Peter Mitchell

  • Tamar Barkay

  • Louis Pasteur

  • Carl Woese and George Fox

  • Paul Berg

Explicación

Pregunta 52 de 81

1

What is the principal Domain of biological organisms within which Operon Theory was developed?

Selecciona una de las siguientes respuestas posibles:

  • E. coli

  • Fungi

  • Eukarya

  • Archaea

  • Bacteria

Explicación

Pregunta 53 de 81

1

Which Biological Domains apply to the below...

Selecciona una o más de las siguientes respuestas posibles:

  • Escherichia coli = Bacteria

  • Cyanobacteria = Bacteria

  • Saccharomyces cerevisiae = Eukarya

  • Cyanobacteria = Archaea

Explicación

Pregunta 54 de 81

1

The use of nitrate as a source of nitrogen to build cells is

Selecciona una o más de las siguientes respuestas posibles:

  • assimilatory nitrate reduction

  • reduction of nitrate to ammonia, whcih is then incorporated into amino acids

  • nitrate respiration

  • denitrification

Explicación

Pregunta 55 de 81

1

Transposons used as mutagens

Selecciona una de las siguientes respuestas posibles:

  • alkylate (e.g., methylate) nitrogen bases of DNA

  • create thymidine dimers

  • distort the DNA backbone and cause reading frameshifts

  • interupt a gene by inserting into it

  • none of these answers are correct

Explicación

Pregunta 56 de 81

1

Which mechanism(s) may protect nitrogenase from denaturation by molecular oxygen?

Selecciona una o más de las siguientes respuestas posibles:

  • fixation of nitrogen under aerobic conditions

  • heterocysts of cyanobacteria that separate nitrogen fixation from oxygenic photosynthesis

  • uncoupling of oxidation from posphorylation in respiratory chain (electron trasport system

  • leghemoglobin

Explicación

Pregunta 57 de 81

1

The Calvin-Benson-Bassam cycle

Selecciona una o más de las siguientes respuestas posibles:

  • catalyzes the oxidation of CO2

  • has metabolic intermediates in common with the oxidative pentose phosphate pathway

  • carboxylates the sugar ribulose 1.5-bisphosphate

  • is found in both eukaryotic and prokarotic domains of life

Explicación

Pregunta 58 de 81

1

The physiological function of anaplerotic CO2 fixation pathways is

Selecciona una o más de las siguientes respuestas posibles:

  • to reoxidize NADH

  • to support autotrophic growth

  • to replenish 4-carbon compounds such as oxaloacetate in the TCA cycle

  • to reverse the TCA cycle

Explicación

Pregunta 59 de 81

1

Which of the below groups includes a genus name that is NOT a diazotroph?

Selecciona una de las siguientes respuestas posibles:

  • Escherichia, Fungi

  • Rhizobium, Sinorhizobium

  • Clostridium, Klebsiella

  • Azotobacter, Anabaena

  • Bradyrhizobium, Spirillum

Explicación

Pregunta 60 de 81

1

Lectins

Selecciona una de las siguientes respuestas posibles:

  • are proteins with an affinity for monosaccharide residues

  • may be used for ABO-typing of blood

  • are involved in host-plant selection for nitrogen-fixing symbioses between bacteria and legumes

  • are produced by legumes

  • all of these answers are correct

Explicación

Pregunta 61 de 81

1

The key enzyme(s) by which bacteria assimilate relatively-LOW concentrations of ammonia is/are

Selecciona una o más de las siguientes respuestas posibles:

  • glutamine synthetase

  • glutamate synthase

  • glutamate dehudrogenase or other amino acid dehydrogenases

  • nitrogenase

Explicación

Pregunta 62 de 81

1

Which of the below enzymes change the covalent structure of DNA?

Selecciona una o más de las siguientes respuestas posibles:

  • DNA polymerase III

  • DNA ligase

  • DNA gyrase

  • DNA helicase

Explicación

Pregunta 63 de 81

1

Who performed experiments using "fluctuation analysis" and Poisson distribution characterizing spontaneous mutations in bacteria?

Selecciona una de las siguientes respuestas posibles:

  • Lois Pasteur

  • Max Delbruck and Salvador Luria

  • Joshua Lederberg

  • Robert Koch and Louis Pasteur

  • Griffith, Avery McLeod and McCarty

Explicación

Pregunta 64 de 81

1

Early, seminal experiments that distinguished between enetic exchange mechanisms of bacteria that require physical contact and those that do not employed which of the below?

Selecciona una de las siguientes respuestas posibles:

  • auxotrophic mutants

  • E. coli

  • U-tube with sintered glass

  • strains of bacteria with multiple biosynthetic deficiencies

  • all of these answers are correct

Explicación

Pregunta 65 de 81

1

Catabolism of a protein bhy any organism requires which first step?

Selecciona una de las siguientes respuestas posibles:

  • hydrolysis of the polypeptide to amino acids

  • deamination

  • breakdown to glucose

  • all of these answers are correct

Explicación

Pregunta 66 de 81

1

"Positive control" regulatory mechanisms include

Selecciona una o más de las siguientes respuestas posibles:

  • catabolite repression

  • repression/co-repression

  • inducible operons

  • attenuation

Explicación

Pregunta 67 de 81

1

What is the utility of the Ames test?

Selecciona una de las siguientes respuestas posibles:

  • Drug resistance of Salmonella typhimurium may be determined

  • Salmonella typhimurium mutation rate may be determined

  • Genes defective in histidine biosynthesis may be corrected

  • Repair of auxotrophic mutants is accomplished

  • an index of potential carcinogenicity of a chemical may be estimated

Explicación

Pregunta 68 de 81

1

Batch-growth kinetics of E. coli grown on lactose and glucose hat become exponential pause for a second lag phase, and then proceed to a second logarithmic phase are

Selecciona una de las siguientes respuestas posibles:

  • a result of a positive-control regulatory meechanism

  • a result of a microbe's "preference"in carbon source

  • a result of a mechanism in which cyclic AMP interacts with an allosteric protein

  • termed "diauxie" or diauxic growth

  • all of these answers are correct

Explicación

Pregunta 69 de 81

1

Regulaion by attenuation requires tight coupling between transcription and translation and, therefore, occurs in

Selecciona una de las siguientes respuestas posibles:

  • eukaryotes

  • prokaryotes

  • fungi and plants

  • algae

  • protozoa

Explicación

Pregunta 70 de 81

1

The theoretical construct describing transfer of information between macromolecules within cells is known as

Selecciona una de las siguientes respuestas posibles:

  • trascriptomics

  • central dogma

  • genomics

  • proteomics

  • bioinformatics

Explicación

Pregunta 71 de 81

1

A contiguous series of genes (cistrons) under transcriptional control of a single operator siteand regulatory protein is known as

Selecciona una de las siguientes respuestas posibles:

  • a regulon

  • a transcription

  • a modulon

  • a transposon

  • an operon

Explicación

Pregunta 72 de 81

1

Regulation by attenuation occurs commonly in which kind of operons?

Selecciona una de las siguientes respuestas posibles:

  • Lac and other sugar-metabolizing operons

  • nitrogen fixation operons

  • Housekeeping gene operons

  • diauxic operons

  • amino acid biosynthesis operons

Explicación

Pregunta 73 de 81

1

Who was awarded the Nobel Prize for elucidating transcriptional regulation in bacteria?

Selecciona una de las siguientes respuestas posibles:

  • Francois Jacob, Andre L'Woff, Jacques Monod

  • Max Delbruck and Salvador Luria

  • Joshuaa Lederberg

  • Robert Koch and Louis Pasteur

  • Griffith, Avery McLeod and McCarty

Explicación

Pregunta 74 de 81

1

Which of the below regions of DNA within an operon are NOT genes/cistrons?

Selecciona una o más de las siguientes respuestas posibles:

  • operator

  • promoter

  • regulator

Explicación

Pregunta 75 de 81

1

Inducible operons

Selecciona una o más de las siguientes respuestas posibles:

  • control transcription of genes with catabolic function

  • control transcription of genes with anabolic/biosynthetic function

  • control transcription of genes with "food" acquisition and digestive function

Explicación

Pregunta 76 de 81

1

Which are cistrons within the Trp operon?

Selecciona una de las siguientes respuestas posibles:

  • control transcription of genes with catabolic fuction

  • control transcription of genes with "food" acquisition and digestive function

  • TrpE, TrpD, Trp C, TrpB, TrpA

  • LacZ, LacY, LacA

Explicación

Pregunta 77 de 81

1

Lower gastrointestinal tracts of vertebrates are anaerobic. Which metabolic pathway(s) is/are responsible for flatulence?

Selecciona una de las siguientes respuestas posibles:

  • fermentation

  • oxygenic photosynthesis

  • anoxygenic photosynthesis

  • TCA cycle

  • aerobic respiration

Explicación

Pregunta 78 de 81

1

The "chemiosmotic theory" of oxidative phosphorylation...

Selecciona una de las siguientes respuestas posibles:

  • provides a unified mechanism for how ATP is made during both aerobic and anaerobic respiration relevant to ALL biological Domains

  • depens on electron transport chains imbedded in an intact plasma- (cytoplasmic) or mitochondrial-membrane

  • explains "photophosphorylation" during the light reactions of phoosynthesis

  • won the Nobel Prize for Peter Mitchell

  • all of these answers are correct

Explicación

Pregunta 79 de 81

1

Which molecular regulatory mechanism(s) allow a bacterium to "decide" whether to use a "preferred" carbon substrate or not?

Selecciona una o más de las siguientes respuestas posibles:

  • catabolite repression

  • repression/corepression

  • inducible operons

  • attenuation

Explicación

Pregunta 80 de 81

1

Mutation has been defined as...

Selecciona una o más de las siguientes respuestas posibles:

  • a stable, heritable change in the DNA sequence of bases

  • a "genetic change that breeds true"

  • changes in the phenotype of an organism

Explicación

Pregunta 81 de 81

1

Which is the correct sequence (in direction of transcription) of genes and regulatory sites in the Lac operon?

Selecciona una de las siguientes respuestas posibles:

  • I-O-P-Z-Y-A

  • I-P-Z-Y-A

  • P-O-LEADER-E-D-C-B-A

  • Z-Y-A-P-O-I

  • LEADER-E-D-C-B-A-P-O

Explicación