Microbial Genetics Ch. 7
Typically, DNA polymerase make mistakes at the rate of 1 out of every 10^10 bases copied. 1 out of every 10^8 bases copied. 1 out of every 10^9 bases copied. 1 out of every 10^6 bases copied. 1 out of every 10^7 bases copied.
1 out of every 10^10 bases copied. DNA polymerase has a very low error rate (1 in every 10 billion copied). This is due to the fact that the enzyme has "proofreading" capability. I can detect if a mismatch has occurred and remove the base that was incorrectly inserted.
How long does it take an Hfr strain of E. coli to transfer its complete chromosome? A. 6.5 minutes B. 100 minutes C. 40 minutes D. 6.5 hours E. 40 hours F. 100 hours
100 minutes
Place the following steps of PCR in order: Annealing of primers Separation of strands Synthesis of new DNA A. 2, 1, 3 B. 3, 1, 2 C. 1, 2, 3 D. 2, 3, 1
2, 1, 3
Place the following events of lagging strand DNA synthesis in order: DNA polymerase synthesizes new DNA strand in the 5' to 3' direction. Primase adds an RNA primer. Okazaki fragments are joined together. RNAse removes the RNA primer. A. 2, 1, 4, 3 B. 2, 1, 3, 4 C. 1, 2, 3, 4 D. 1, 2, 4, 3
2, 1, 4, 3
Put the following events of conjugation in order: Fusion of the cell membranes Attachment of the sex pilus Transfer of the F factor Pulling of donor and recipient cells together A. 2, 4, 1, 3 B. 3, 2, 1, 4 C. 4, 2, 1, 3 D. 2, 1, 4, 3
2, 4, 1, 3
Put the following events of PCR in order: Repeat 30+ times. Denature at 94°C. Extend at 72°C. Prime at 60°C. A. 4, 3, 2, 1 B. 2, 3, 4, 1 C. 2, 4, 3, 1 D. 1, 2, 4, 3
2, 4, 3, 1
According to the chart, how many amino acids are coded for by codons? A. 20 B. 61 C. 64 D. 3
20
How many amino acids are used by cells to make proteins? 15 21 64 25
21
How many codons code for the termination of transcription? A. 61 B. 64 C. 1 D. 3
3
How many nucleotides make up the anticodon? Is it A) 3 or B) 4.
3
Put the following events of conjugation in order: Transfer of the DNA Fusion of the cell membranes Pulling of donor and recipient cells together A. 3, 2, 1 B. 2, 3, 1 C. 1, 3, 2 D. 1, 2, 3
3, 2, 1
How many different types of nucleotides are found in the DNA molecule? Is it A) 3 or B) 4.
4
Ribosomes move along the mRNA in which direction? A. 3' to 5' B. 5' to 3' C. either 5' to 3' or 3' to 5'
5' to 3'
Which of the following is an example of a nucleoside analog? A. nitrous acid B. arcidine orange C. 5-bromouracil D. benzopyrene E. ethidium bromide
5-bromouracil
Which of the following events occurs during transcription? mRNA binds to a ribosome in the cytoplasm. A molecule of RNA is formed based on the sequence of nucleotides in DNA. Those segments of the RNA strand that do not actually code for the protein are removed. A cap is added to the RNA molecule. The message in mRNA is translated into a protein.
A molecule of RNA is formed based on the sequence of nucleotides in DNA The message in mRNA is translated into a protein during the process of translation.
What is the order of ribosomal sites that a charged tRNA molecule passes through? A. A site, E site, P site B. P site, A site, E site C. E site, A site, P site D. E site, P site, A site E. A site, P site, E site
A site, P site, E site
Which statement about conjugation is true? A. Conjugation is a process of bacterial reproduction. B. After conjugation, each cell involved has a copy of the shared DNA. C. Conjugation can occur between two cells separated at a great distance.
After conjugation, each cell involved has a copy of the shared DNA.
Which of the following can result once the recombinant DNA molecule has been made? A. It is inserted into a host cell. B. It is copied many times inside a host cell. C. It can be transcribed and then translated into a desired protein. D. All of the above actions can result. E. None of the above actions can result.
All of the above actions can result.
What is the function of the enzyme transposase? A. It cuts the DNA so the transposon can leave its current position. B. It cuts the DNA at the new site for a transposon. C. It covalently links the transposon to the new DNA site. D. All of the above answers apply. E. None of the above answers apply.
All of the above answers apply.
Which of the following statements regarding the induction of the lac operon is true? A. Allolactose serves as an inducer. B. The inducer acts by turning off the repressor. C. Induction of the operon ceases when lactose is absent from the system. D. All of the above statements apply. E. None of the above statements apply.
All of the above statements apply.
Which of the following statements are true? A. S strains are capable of causing disease in mice. B. R strains are unable to cause disease in mice. C. R strains do not produce a capsule. D. All of the above statements are true. E. None of the above statements are true
All of the above statements are true.
Which of the following statements regarding RNA polymerase is true? A. RNA polymerase reads the template strand of DNA. B. RNA polymerase adds nucleotides to the 3' end of the growing RNA molecule. C. RNA polymerase binds to the promoter region of the gene prior to starting RNA synthesis. D. All of the above statements are true. E. None of the above statements are true.
All of the above statements are true.
Which of the following statements regarding operons is true? A. Inducible operons are transcribed only when they are activated. B. Repressible operons are always transcribed unless they are deactivated by a repressor. C. The structural genes of an operon typically have the same biochemical function in the cell. D. All of the above statements are true. E. None of the above statements are true.
All of the above statements are true.
What is/are the role(s) of dNTPs in a PCR? A. They are the monomers for the DNA strand to be synthesized. B. They provide energy for the DNA polymerization to occur. C. Both of the above answers apply. D. Neither of the above answers applies.
Both of the above answers apply.
All of the following are possible base pair combinations in nucleic acids EXCEPT __________. A-T G-C A-U C-T
C-T This is a base pair involving two pyrimidine bases, which would not form readily in the cell.
Which is a product of replication? Is it A) DNA or B) RNA.
DNA
Which one of the following does not play a role in translation? Amino acids tRNA Ribosomes DNA Anticodon
DNA DNA contains the instructions for making proteins, but these instructions are transcribed to RNA before translation occurs.
All of the following are true statements concerning the structure of DNA EXCEPT __________. DNA contains the sugar deoxyribose DNA contains the nitrogenous bases A, C, G, and U the two strands of a DNA molecule are held together by hydrogen bonds the two strands of a DNA molecule are antiparallel to each other
DNA contains the nitrogenous bases A, C, G, and U DNA contains thymine (T) instead of uracil (U).
Transposons are _________________________. A. enzymes that can move from one location in the DNA to another. B. DNA fragments that can move from one location in the DNA to another. C. DNA fragments that move from one cell to another. D. proteins that move from one cell to another.
DNA fragments that can move from one location in the DNA to another.
What is the role of DNA helicase in DNA replication? A. DNA helicase synthesizes new strands of DNA. B. DNA uses DNA to get energy from ATP. C. DNA helicase uses the energy from ATP to break the hydrogen bonds between two DNA strands, thereby "unzipping" the molecule. D. DNA helicase stabilizes the single strands of DNA during replication.
DNA helicase uses the energy from ATP to break the hydrogen bonds between two DNA strands, thereby "unzipping" the molecule.
Which statement about DNA replication is FALSE? DNA ligase adds nucleotides to the lagging strand. The lagging strand is made of a series of pieces that must be joined together to make a continuous strand. DNA polymerase builds a new strand by adding DNA nucleotides one at a time. Because the two strands of parental DNA run in opposite directions, the new strands must be made in different ways. The two strands of parental DNA are separated during DNA replication.
DNA ligase adds nucleotides to the lagging strand. This statement is FALSE. DNA ligase seals the gaps between segments of DNA in the lagging strand. It does not add nucleotides to the lagging stran
The molecule that seals the gaps between the pieces of DNA in the lagging strand is DNA ligase. the leading strand. the replication fork. RNA. DNA polymerase.
DNA ligase. DNA ligase seals the gaps between the pieces of DNA in the lagging strand, turning it into a continuous strand.
Which enzyme(s) can synthesize new strands of DNA? A. primase B. DNA polymerase ligase C. A and B D. all of the above
DNA polymerase
Which of the following synthesize(s) new strands of DNA? The lagging strand The leading strand The origins of replication DNA polymerases Parental DNA
DNA polymerases DNA polymerases build new strands of DNA by adding DNA nucleotides one at a time.
The process of copying DNA prior to cell replication is known as _____________. A. RNA replication. B. DNA synthesis. C. DNA replication. D. DNA transcription. E. DNA translation.
DNA replication.
Why are F- cells unable to spread the fertility factor? A. F- cells have too much genetic information to use, making it unlikely for them to make the fertility factor. B. Hfr cells prevent F- recipients from mating. C. F- cells rarely receive a complete copy of the fertility factor during conjugation. D. They have only a chromosome c
F- cells rarely receive a complete copy of the fertility factor during conjugation.
True or False? The transfer of genetic information between cells involving a sex pilus is called transformation.
False
DNA synthesis occurs in which direction? A. From 3' to 5' on both the leading and lagging strands. B. From 5' to 3' on the lagging strand and 3' to 5' on the leading strand. C. From 5' to 3' on the leading strand and 3' to 5' on the lagging strand. D. From 5' to 3' on both the leading and lagging strands.
From 5' to 3' on both the leading and lagging strands.
What is a potential source of mutations from ionizing radiation? A. Ionizing radiation can result in nucleoside analogues mispairing with the normal DNA sequence. B. Ionizing radiation can result in the formation of thymine dimers. C. Ions and free radicals resulting from ionizing radiation can break chromosomes. D. Ionizing radiation can cause the addition or removal of bases, resulting in a mutation.
Ions and free radicals resulting from ionizing radiation can break chromosomes.
What is the role of tryptophan in the trp operon? A. It activates the repressor proteins. B. It causes the transcription of the regulatory gene. C. It is needed to produce the structural genes. D. It binds to the operator region.
It activates the repressor proteins.
Why is a temperature of 94oC required during PCR? A. It allows for the strands of the target DNA to separate. B. This is the optimum temperature for the thermostable DNA polymerase. C. It sterilizes the reaction to avoid microbial contamination. D. It allows the primers to attach to the target DNA.
It allows for the strands of the target DNA to separate.
What is unique about the DNA polymerase in PCR? A. It does not require primers. B. It can withstand the high temperatures needed for PCR. C. It synthesizes DNA from the 3' direction to the 5' direction. D. It can separate strands of DNA.
It can withstand the high temperatures needed for PCR.
How does the DNA polymerase know which nucleotide triphosphate to add to the growing strand? A. It hydrogen-bonds the nucleotide to the RNA primer made by primase, pairing adenines to thymines and guanines to cytosines. B. It does not; it is a random process that results in genetic diversity for the offspring. C. It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to thymines and guanines to cytosines. D. It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to cytosines and guanines to thymines.
It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to thymines and guanines to cytosines.
When is the regulatory gene transcribed? A. It is transcribed only when the regulatory protein is not bound to the operator. B. it is transcribed only in the absence of lactose. C. It is transcribed only in the presence of lactose. D. It is always transcribed.
It is always transcribed.
What is unique about the DNA transferred between two cells during conjugation? A. It is transferred as a double strand. B. It is briefly outside of the cells during conjugation. C. It is transferred as a single strand. D. B and C E. none of the above
It is transferred as a single strand.
Why is primase essential for DNA replication? A. It provides a 3' end of the newly synthesized strand, allowing DNA polymerase to begin copying DNA. B. It repairs the gaps between DNA fragments during lagging strand synthesis. C. It removes the RNA left from the DNA replication process. D. It provides the RNA that is an essential part of the newly copied chromosome.
It provides a 3' end of the newly synthesized strand, allowing DNA polymerase to begin copying DNA.
Which of the following is NOT a function of RNA? It serves as the genome of some viruses. It provides energy for cells. It serves as a structural component of ribosomes. It catalyzes protein synthesis.
It provides energy for cells.
Which of the following happens to initiate specialized phage transduction? A. Bacteriophage enters lysogeny. B. Prophage integrates into the host genome. C. The host cell lyses. D. Prophage integrates into the host genome AND bacteriophage enters lysogeny. E. Prophage integrates into the host genome AND the host cell lyses.
Prophage integrates into the host genome AND bacteriophage enters lysogeny.
How does protein-dependent termination differ from protein-independent termination? A. Protein-dependent termination does not dislodge the RNA polymerase from the DNA. B. Protein-dependent termination does not produce RNA. C. Protein-dependent termination uses a promoter to end transcription. D. Protein-dependent termination involves the use of a protein to end transcription.
Protein-dependent termination involves the use of a protein to end transcription.
Which of these is NOT true of mutations? Mutations are rare events. Ionizing radiation can cause breaks in chromosomes, as well as mutations. Pyrimidine dimers are mutations caused mostly by chemical mutagens. Bacteria have the ability to repair some mutations.
Pyrimidine dimers are mutations caused mostly by chemical mutagens. If mutations were common events, organisms could not live or effectively reproduce themselves.
How does replicative transposition differ from cut-and-paste transposition? A. Replicative transposition results in multiple copies of the transposon in the DNA; cut-and-paste transposition has only one copy. B. Replicative transposition is faster than cut-and-paste transposition. C. Replicative transposition integrates into the host genome; cut-and-paste transposition does not. D. Replicative transposition makes use of the enzyme transposase; cut-and-paste transposition does not.
Replicative transposition results in multiple copies of the transposon in the DNA; cut-and-paste transposition has only one copy.
During DNA replication, which nucleotide will pair with an A nucleotide in the parental DNA? G A C T U
T During DNA replication, A binds with T.
What reason most likely explains the recovery of S strain from a mouse injected with heat-killed S strain mixed with living R strain? A. The S strain fused with the R strain, making it resistant. B. The S strain was revived by the presence of the host's immune system. C. The R strain picked up the S-strain DNA, enabling it to produce capsules. D. The R strain picked up the capsule from the S strain.
The R strain picked up the S-strain DNA, enabling it to produce capsules.
Where is the codon found? Is it A) on the tRNA or B) on the mRNA.
The answer is B) on the mRNA. The codon is found on the mRNA and the anticodon is on the tRNA.
In which process do two bacterial cells make direct contact and share genetic information through a sex pilus? Is it A) conjugation or B) transduction.
The correct answer is A) conjugation. Conjugation is the transfer of genetic material from one cell to another involving cell-to-cell contact.
What forms when DNA is exposed to UV light? Is it A) thymine dimers or B) operons.
The correct answer is A) thymine dimers. Thymine dimers form when DNA is exposed to UV light.
Which process uses mRNA as a template in the synthesis of protein? Is it A) translation or B) transduction?
The correct answer is A) translation. Translation takes the information in the mRNA and synthesizes proteins.
What do we call the sequence of three nucleotides on the tRNA molecule that pairs with the mRNA molecule? Is it the A) codon or B) anticodon.
The correct answer is B) anticodon. The anticodon on the tRNA recognizes the codon on the mRNA.
Which type of chemical bond connects the base pairs in DNA? Is it A) covalent or B) hydrogen.
The correct answer is B) hydrogen. Hydrogen bonds link complementary bases in the DNA molecule.
What do we call the process of copying DNA prior to cell division? Is it A) transcription or B) replication
The correct answer is B) replication. Replication of DNA creates identical DNA molecules to be passed to the next generation of cells.
Which type of RNA brings the correct amino acid to the ribosome? Is it A) mRNA or B) tRNA.
The correct answer is B) tRNA. Transfer RNA is the type of RNA that brings amino acids to the ribosomal site where they are incorporated into proteins.
In which process is genetic information transferred between bacterial cells by a bacteriophage? Is it A) transformation or B) transduction.
The correct answer is B) transduction. In transduction, a bacteriophage carries the genetic information from one cell to another.
Which statement about DNA replication is CORRECT? The lagging strand is built continuously. DNA ligase helps assemble the leading strand. The lagging strand is one of the strands of parental DNA. The leading strand is one of the strands of parental DNA. The leading strand is built continuously, and the lagging strand is built in pieces.
The leading strand is built continuously, and the lagging strand is built in pieces. The leading and lagging strands are the new strands of DNA made during DNA replication. The leading strand is built continuously, and the lagging strand is built in pieces, called Okazaki fragments.
Which of the following statements concerning DNA replication is true? -The leading strand of DNA replication requires only one RNA primer. -The lagging strand of DNA replication requires multiple RNA primers. -The lagging strand of DNA replication requires only one RNA primer. -The leading strand of DNA replication does not require an RNA primer.
The leading strand of DNA replication requires only one RNA primer.
What is meant by semiconservative replication? A. Both the new DNA molecules are made up of new DNA. B. The newly made DNA strand is made entirely of new DNA, while the parental DNA is conserved. C. The new copies of DNA contain one original strand of DNA and one new strand of DNA. D. Both the new DNA and the parental DNA remain connected during DNA replication.
The new copies of DNA contain one original strand of DNA and one new strand of DNA.
What might happen if the cell does not have RNAse? A. DNA polymerase would not have a 3' to begin DNA synthesis. B. The newly made chromosome would consist of DNA and RNA molecules. C. There would be gaps of missing DNA throughout the newly synthesized DNA. D. The hydrogen bonding between the DNA strands would all be broken.
The newly made chromosome would consist of DNA and RNA molecules.
Which of the following statements about PCR is true? A. The phosphodiester bond between each nucleotide is broken during the denaturation step. B. After each round of PCR, you will have one new strand of target DNA. C. After 30 rounds of PCR, the target DNA has been amplified several thousand times. D. The number of DNA doubles after each cycle.
The number of DNA doubles after each cycle.
How can a mismatch repair enzyme detect which strand contains the correct DNA sequence? A. The original strand will likely have a methyl group attached, while the newly mutated strand will not. B. Mismatch repair enzymes look for a bulge in the DNA caused by the mutation. C. The mutated sequence has dimers occurring between adjacent bases. D. The mutated sequences are easily detected in the presence of light.
The original strand will likely have a methyl group attached, while the newly mutated strand will not.
What must occur for an organism to pass its genetic information on to its offspring? A. The parental chromosome must be given to the offspring. B. A novel DNA chromosome must be made by the parent cell and given to its offspring. C. The host chromosome must be degraded. D. The parent must copy its own DNA and provide a copy to its offspring.
The parent must copy its own DNA and provide a copy to its offspring.
Why is E. coli considered the model of bacterial conjugation? A. E. coli is the only bacterium capable of performing conjugation between all types of bacteria. B. E. coli is the only bacterium capable of performing conjugation with eukaryotic cells. C. E. coli is the only bacterium capable of conjugation. D. The process of conjugation is best characterized in E. coli.
The process of conjugation is best characterized in E. coli.
Which of the following statements regarding the lac operon is true? A. The operator region codes for the structural genes involved in lactose metabolism. B. When lactose is available, the repressor proteins are inactive. C. The repressor proteins bind to the operator, preventing RNA polymerase from transcribing the structural genes. D. Galactose is an inducer of the lac operon.
The repressor proteins bind to the operator, preventing RNA polymerase from transcribing the structural genes.
Why is the transcription of structural genes of the trp operon turned off in the presence of tryptophan? A. Tryptophan RNA polymerase from finding the promoter of the trp operon, preventing structural gene transcription. B. Tryptophan is the repressor that binds to the operator, preventing transcription. C. The structural genes are used to make tryptophan, which would not be needed if tryptophan is available. D. Tryptophan has no effect on the transcription of the structural genes.
The structural genes are used to make tryptophan, which would not be needed if tryptophan is available.
Which of the following statements is false regarding the trp operon? A. Activated repressor proteins bind to the operator region, preventing RNA polymerase from transcribing the structural genes. B. The repressor gene is always transcribed. C. The structural genes are used to synthesize tryptophan. D. The structural genes of the trp operon are transcribed only in the presence of tryptophan.
The structural genes of the trp operon are transcribed only in the presence of tryptophan.
Which of the following statements regarding the trp operon is true? A. The regulatory gene is not transcribed in the presence of the repressor. B. The trp operon is always activated unless deactivated by a repressor. C. The operator region produces the mRNA that codes for the repressor. D. Repressor proteins are inactivated by the presence of the repressor.
The trp operon is always activated unless deactivated by a repressor.
Why do S strains escape killing by host phagocytes? A. They are resistant to heat. B. They are genetically engineered to be resistant to killing. C. They are encapsulated. D. They are naturally competent.
They are encapsulated.
Which of the following statements regarding Okazaki fragments are true? -They are typically 1000 nucleotides in length. -They are found on the lagging strand of DNA replication. -They are composed of RNA. -They are found on the leading strand of DNA replication.
They are typically 1000 nucleotides in length. They are found on the lagging strand of DNA replication.
Why is a complex transposon containing an antibiotic resistance gene more likely to be copied than a simple insertion sequence when the host reproduces? A. They are larger. B. They confer a survival advantage for the host. C. They allow host DNA replication to occur. D. They have more active transposase.
They confer a survival advantage for the host.
What characteristics do F+ and F- cells share? A. They each have an F plasmid. B. They each produce sex pili. C. They each contain a chromosome. D. all of the above E. none of the above
They each contain a chromosome.
What is unique about complex transposons? A. They contain insertion sequences. B. They have two simple transposons with another DNA sequence between them. C. They code for a transposase. D. They always integrate the DNA sequence in between the two simple transposons into the host DNA.
They have two simple transposons with another DNA sequence between them.
What is the function of stabilizing proteins? A. They synthesize new strands of DNA. B. They form the replication fork. C. They hold the separated strands apart and prevent their degredation. D. They use ATP to break the hydrogen bonds between the strands of DNA.
They hold the separated strands apart and prevent their degredation.
What is the function of the connector proteins? A. They enable one parental DNA strand and one newly synthesized DNA strand to be held together. B. They link the leading strand DNA polymerase and the lagging strand DNA polymerase together. C. They allow DNA synthesis to occur from the 3' to 5' direction. D. They produce the Okazaki fragments.
They link the leading strand DNA polymerase and the lagging strand DNA polymerase together.
True or False? A tRNA is involved in bringing the amino acid to the mRNA.
True
True or False? In a DNA molecule, guanine pairs with cytosine.
True
An operon is __________. a single molecule that regulates transcription a group of genes that share the same promoter the DNA sequence that results from conjugation a sequence of genes found in both prokaryotes and eukaryotes
a group of genes that share the same promoter
The transfer of DNA between bacterial cells is often facilitated by which of the following? fimbriae a flagellum the nucleus a pilus
a pilus
What DNA molecule is transferred between cells during conjugation between an F+ and an F- cell? A. a double-stranded F plasmid B. a single strand of the chromosome C. a double-stranded chromosome D. a single-stranded F plasmid
a single-stranded F plasmid
Insertion sequences are composed of _____________. A. a transposase gene flanked by inverted repeats. B. an inverted repeat flanked by transposase genes. C. a transposase gene and host DNA. D. a transposase gene flanked by random sequence.
a transposase gene flanked by inverted repeats.
The replication fork moves ___________. A. opposite the direction of the DNA helicase. B. away from the direction of newly synthesized DNA. toward the stabilizing proteins. C. ahead of the newly synthesized DNA.
ahead of the newly synthesized DNA.
For which of the following applications can PCR be used? A. sequencing DNA B. making copies of a gene to be put into another organism C. identifying traits that may lead to a genetic disorder D. all of the above E. none of the above
all of the above
The process of generalized transduction ___________. A. requires a lytic bacteriophage. B. utilizes any fragment of the bacterial chromosome. C. results from sloppy packaging of DNA by bacteriophage. D. all of the above E. none of the above
all of the above
Which of the following are genetic elements found in an operon? A. operator region B. structural genes C. promoter D. all of the above
all of the above
Which of the following is a product of transcription? A. mRNA B. rRNA C. tRNA D. all of the above E. none of the above
all of the above
Which of the following is involved in translation? A. ribosomes B. mRNA C. amino acids D. all of the above E. none of the above
all of the above
The fertility factor is also known as __________. A. an F plasmid. B. conjugation. C. a sex pilus. D. a chromosome.
an F plasmid.
All of the following are components of a nucleotide EXCEPT __________. a phosphate group a pentose sugar a nitrogenous base an amino group
an amino group Nucleotides are composed of a phosphate group, a pentose sugar, and a nitrogenous base.
Where does the activation and repression of an operon occur? A. at the promoter region B. at the operator region C. at the structural genes D. all of the above E. none of the above
at the operator region
Release factors _________________________. A. are coded by stop codons. B. bind to the A site. C. keep the ribosomal subunits together. D. bind to the A site AND are coded by stop codons. E. bind to the A site AND keep the ribosomal subunits together. F. none of the above
bind to the A site AND are coded by stop codons.
How does an F+ cell become an Hfr cell? A. by integrating the F plasmid into the chromosome B. by mating with an F- cell C. by mating with another F+ cell D. by losing its F plasmid
by integrating the F plasmid into the chromosome
Cells that are naturally able to take up DNA from their environment are said to be ___________________. A. recombinant. B. R strains. C. S strains. D. competent.
competent
Which of these terms does NOT relate directly to conjugation? pili F+ competent Hfr
competent Hfr stands for "High Frequency of Recombination" and is a type of cell that has its F plasmid integrated within its chromosome.
Which type of transposon would contain an antibiotic resistance gene? A. both B. neither C. complex transposons D. simple transposons
complex transposons
Which of the following is not a constituent of PCR? A. dUTP B. target DNA C. DNA polymerase D. DNA primers E. dATP
dUTP
What serves as the template for DNA replication? A. each of the original DNA strands B. RNA from the cell C. the new DNA strands D.proteins that are associated with DNA replication
each of the original DNA strands
Which of the repair mechanism(s) requires assistance from DNA polymerase to make the correction? A. light-repair mechanism B. excision-repair mechanism C. mismatch-repair mechanism D. excision-repair mechanism AND mismatch-repair mechanism E. none of the above
excision-repair mechanism AND mismatch-repair mechanism
Which gene would transfer quickest during conjugation for this Hfr strain? A. purA B. leu C. fertility factor D. lac E. argE
fertility factor
What type of mutation can change all subsequent amino acids following it? C. silent mutation B. missense mutation C. nonsense mutation D. frameshift mutation
frameshift mutation
Ethidium bromide can result in _________________. A. chromosomal breaks. B. frameshift mutations via insertion or deletion of nucleotides. C. base mismatching during DNA replication. D. thymine dimers.
frameshift mutations via insertion or deletion of nucleotides.
What does Hfr stand for? A. high fertility recognition B. high fertility recipient C. high fertility recombination D. high frequency of recombination
high frequency of recombination
In general, higher levels of transcription lead to ______________________. A. lower amounts of DNA. B. higher amounts of protein. C. higher amounts of DNA. D. lower amounts of protein. E. higher amounts of stem loops.
higher amounts of protein.
All of the following are associated with bacterial DNA replication EXCEPT __________. Okazaki fragments methylation semiconservative manner histones
histones Bacteria do not have histone proteins, but do have proteins that are similar to histones.
Ribosomes __________. are composed of three subunits: A, E, and P in bacteria are the same type as those found in chloroplasts and mitochondria are responsible for transcription are comprised of carbohydrate and protein
in bacteria are the same type as those found in chloroplasts and mitochondria Ribosomes are responsible for protein synthesis (translation).
Where do mutations occur? Is it A) in the DNA or B) in the protein.
in the DNA
Which of the following would be a fate of a bacterium infected by a generalized transducing bacteriophage? A. lysis B. integration of the packaged DNA into the host chromosome C. production of more transducing phage D. all of the above
integration of the packaged DNA into the host chromosome
A region of DNA in which the sequence of nucleotides is identical to an inverted sequence on the complementary strand is known as a(n) __________. A. inverted repeat. B. transposase. C. insertion sequence. D. transposon.
inverted repeat.
X-rays would be considered which type of mutagen? A. nonionizing radiation B. nucleoside analog C. nucleotide-altering chemical D. ionizing radiation
ionizing radiation
Transduction __________. is a segment of DNA that moves from one location in a DNA molecule to another location occurs when a bacterium picks up DNA from its environment and incorporates it into its genome is a type of gene transfer that is carried out by bacteriophage describes the copying of DNA onto mRNA prior to protein synthesis
is a type of gene transfer that is carried out by bacteriophage This description refers to transformation, not transduction.
The replication fork __________________. A. is what results if the DNA strands begin to degrade. B. is the point where DNA helicase is "unzipping" the double-stranded DNA molecule. C. is the point where stabilizing proteins bind the single strands of DNA. D. is another term for DNA replication.
is the point where DNA helicase is "unzipping" the double-stranded DNA molecule.
The chromosomes of a bacterial cell __________. has several origins of replication is usually circular is located in the nucleus contains a single strand of DNA
is usually circular Prokaryotic cells do not have a nucleus.
All of the following are characteristics of a sigma factor, EXCEPT __________. sigma factors vary in their strength of attraction it is used to help to control the amount of transcription it is necessary for recognition of a promoter by RNA polymerase it is a part of the promoter
it is a part of the promoter There is about a million-fold difference in attraction between the strongest and the weakest sigma factors.
Enzymes known as photolyases are involved in which type of repair? A. light-repair mechanism B. excision-repair mechanism C. mismatch-repair mechanism D. all of the above E. none of the above
light-repair mechanism
Which of the following repair mechanism(s) does not involve the removal of nucleotides? A. light-repair mechanism B. excision-repair mechanism C. mismatch-repair mechanism D. all of the above E. none of the above
light-repair mechanism
Which of the following repair mechanisms might be involved in repairing a mutation that results from exposure to UV light? A. light-repair mechanism B. excision-repair mechanism C. mismatch-repair mechanism D. light-repair mechanism AND excision-repair mechanism E. all of the above
light-repair mechanism AND excision-repair mechanism
Which of the following is not a part of the initiation complex? A. mRNA B. tRNA charged with Met C. tRNA charged with Gly D. small ribosomal subunit E. large ribosomal subunit
mRNA
Which of the following is the copy of a DNA sequence used to make protein? A. mRNA B. tRNA C. rRNA
mRNA
Which of the following does not occur during RNA processing? Segments of the RNA strand that do not actually code for the protein are removed. mRNA attaches to the small subunit of a ribosome. Segments of RNA that do code for the protein are reconnected. Adenine nucleotides are added to the end of the RNA strand, forming a tail. A modified guanine nucleotide is added to the beginning of the RNA strand as a cap.
mRNA attaches to the small subunit of a ribosome. Segments of RNA that do code for the protein are reconnected during RNA processing.
Which of the following is a correct statement about mRNA? mRNA moves from the nucleus to the cytoplasm following RNA processing. mRNA binds directly to amino acids during translation. mRNA is transcribed from DNA in the cytoplasm. Segments of mRNA that code for protein are removed before translation. mRNA includes a cap that consists of extra adenine nucleotides.
mRNA moves from the nucleus to the cytoplasm following RNA processing. It is segments of the RNA strand that do not code for protein that are removed before translation.
A chemical that can increase the rate of mutations is called a _______________________. A. carcinogen. B. deletion. C. insertion. D. mutagen.
mutagen.
Which of the following is a characteristic of an F- cell? A. ability to synthesize sex pili B. presence of a fertility factor C. ability to mate with an F- cell D. all of the above E. none of the above
none of the above
A mutation that results in the presence of a stop codon in the middle of the genetic code is a _____________. A. frameshift mutation. B. nonsense mutation. C. missense mutation. D. silent mutation.
nonsense mutation.
Which of the following pairs are incorrectly matched? nonsense mutation: results in change in amino acid point mutation: only one base pair is affected frameshift mutation: insertion of nucleotides silent mutation: no change in phenotype
nonsense mutation: results in change in amino acid
Pyrimidines are molecules used in the synthesis of which of the following? lipids carbohydrates nucleic acids proteins
nucleic acids
What typically results from conjugation between an Hfr cell and an F- cell? A. one Hfr cell and one F- cell B. two F- cells C. two Hfr cells
one Hfr cell and one F- cell
How frequently does an error occur in DNA replication in the absence of a mutagen? A. one error for every 100,000 nucleotides copied B. one error for every 1,000,000,000 nucleotides copied C. one error for every 10,000,000 nucleotides copied D. one error for every 10,000 nucleotides copied E. one error for every 1,000,000 nucleotides copied
one error for every 1,000,000,000 nucleotides copied
Which of the following is used to make ribosomes? A. tRNA B. mRNA C. rRNA
rRNA
PCR __________________________________. A. is a process that only microorganisms can perform. B. rapidly increases the number of copies of a piece of DNA. C. makes billions of novel DNA sequences from only one original sequence.
rapidly increases the number of copies of a piece of DNA.
Which of the following terms could describe the newly infected host of a specialized transducing bacteriophage? -recombinant cell -prophage -donor cell -recipient cell
recipient cell & recombinant cell
A cell that has incorporated new DNA as part of its own is termed a __________. A. recombinant. B. donor. C. recipient.
recombinant
What does the inducer bind to in the lac operon system? A. repressor proteins B. the operator region of the DNA C. RNA polymerase D. the promoter region of the DNA
repressor proteins
Which of the following cuts DNA at specific sequences? A. DNA ligase B. plasmids C. restriction enzyme
restriction enzyme complementary sticky ends
The site of translation is the plasma membrane. ribosomes in the cell cytoplasm. the Golgi apparatus. the cell nucleus. ribosomes in the cell nucleus.
ribosomes in the cell cytoplasm.
Which term describes DNA replication? Is it A) semiconservative or B) conservative.
semiconservative
Which mutation is the least likely to be harmful to a cell? A. silent mutation B. frameshift mutation C. nonsense mutation D. missense mutation
silent mutation
Base pair substitutions can result in what type(s) of mutation? A. nonesense mutation B. missense mutation C. silent, frameshift, and missense D. silent mutation E. silent, nonsense, and missense F. frameshift mutation
silent, nonsense, and missense
Which of these is not correctly matched with its function? P site: holds tRNA and growing polypeptide chain ribozyme: forms peptide bond between amino acids tRNA: delivers an amino acid to the ribosome stop codon: signals the termination of transcription
stop codon: signals the termination of transcription The P site in the ribosome is the location where a tRNA is holding the growing polypeptide chain
The anticodon sequence is found on the __________. A. ribosome. B. DNA. C. tRNA. D. mRNA. E. amino acid.
tRNA
Which of the following is involved in bringing amino acids to the ribosomes? A. mRNA B. rRNA C. tRNA
tRNA
In which of the following locations in a eukaryotic cell would we NOT find DNA molecules? mitochondria chloroplasts the nucleus the Golgi body
the Golgi body
Generalized transduction is initiated by ___________. A. binary fission of the host cell. B. the lysogenic cycle of viral replication. C. the lytic cycle of viral replication. D. the release of newly synthesized viruses.
the lytic cycle of viral replication.
What is the target of the activated repressor protein? A. tryptophan B. structural genes C. the operator region of the operon D. the promoter region of the operon
the operator region of the operon
Which of the following is packaged by the bacteriophage A. the phage DNA with some of the host DNA B. the phage DNA alone C. the host DNA alone
the phage DNA with some of the host DNA
Translation is _________________________. A. the process of making protein from DNA. B. the process of making protein from RNA. C. the process of making RNA from DNA. D. the process of making DNA from RNA.
the process of making protein from RNA.
Which genetic element codes for the repressor protein? A. lacZ B. the operator region C. lacY D. the promoter region E.the regulatory gene
the regulatory gene
hich of the following would be an example of horizontal gene transfer? A. the fusion of a sperm and egg cell during fertilization B. a cell transferring a copy of its genome during mitosis C. a bacterium transferring a copy of its genomic DNA to daughter cells during binary fission D. the transfer of DNA from one bacterium to another
the transfer of DNA from one bacterium to another
Transduction is _____________________. A. the destruction of host DNA by a bacteriophage. B. the transfer of phage DNA from one host to another via a bacteriophage. C. the infection of a bacterium by a lytic phage. D. the transfer of bacterial DNA from one host to another via a bacteriophage.
the transfer of bacterial DNA from one host to another via a bacteriophage.
The device used to achieve the varying temperatures required for PCR is called a(n) _______________. A. thermocycler. B. thermocopier. C. denaturer. D. thermoextender. E. PCR cycler.
thermocycler.
Each amino acid in the primary structure of a protein is coded for by __________. two nucleotides in mRNA six nucleotides in mRNA is coded for by one nucleotide in mRNA three nucleotides in mRNA
three nucleotides in mRNA Each nucleotide triplet (codon) codes for a single amino acid.
Why must the recipient plasmid be cut with the same restriction enzyme? A. to prevent the donor from receiving the same genetic information B. to allow for a site in the plasmid for the donor DNA to attach C. to remove the donor DNA from the plasmid D. all of the above E. none of the above
to allow for a site in the plasmid for the donor DNA to attach
The role of transcription is ___________________. A. to copy DNA prior to cell division. B. to assemble amino acids into proteins. C. to copy the information stored in DNA into RNA. D. to pass genetic information from one cell to another.
to copy the information stored in DNA into RNA.
What is the ultimate goal of recombinant DNA technology? A. to add desirable genes B. to improve the organism C. to add plasmids D. to remove undesirable genes
to improve the organism
What is the purpose of bacterial conjugation? A. to transfer DNA between two living cells B. to allow cells to take up DNA from their environment C. to bring two cells in contact with each other
to transfer DNA between two living cells
What is the process when a strand of RNA is synthesized from a DNA template? Is it A) translation or B) transcription.
transcription
Which of the following is NOT a type of horizontal gene transfer? A. conjugation B. transformation C. transduction D. transcription
transcription
A bacterium that takes up DNA from its surrounding environment has undergone __________. transduction translation transformation transcription
transformation Transduction involves the transfer of DNA from one bacterium to another by a bacteriophage.
Following conjugation between a donor and a recipient, what cell types are present? A. two F- cells B. an F+ cell and an F- cell C. two F+ cells
two F+ cells
An amino acid is considered charged ____________. A. when it enters the P site. B. when it is bound to its correct tRNA. C. when it leaves the E site. D. when it binds to the mRNA.
when it is bound to its correct tRNA.
