Ch. 8 Study Questions

Which mutation is the least detrimental to the DNA? A) one nucleotide deletion B) three nucleotide deletions C) four nucleotide deletions D) two nucleotide deletions

B) three nucleotide deletions

Almost always the template strand on DNA will consistently begin with A. TUG B. AUG C. ATG D. UAT

B. AUG

Who established that there was a transforming principle in bacterial genetics through an experiment involving pneumococci performed in 1928? A. Crick B. Griffith C. McCarty D. Ames

B. Griffith

Phage DNA as the property of: a. Encoding proteins to important bacteria b. Moving to different location in DNA in the same cell c. Coding for only non-essential genetic information d. Coding for only essential genetic information

a. Encoding proteins to important bacteria

Which is NOT a repair mechanism for a spontaneous mutation? a) proofreading by DNA polymerase b) action of glycosylase c) SOS repair d) mismatch repair

c) SOS repair

Bacterial cells are competent when: a) They can grow on their own without added nutrients b) They have eliminated all of their mutation deficiencies (ex. Leu-, Thr-) c) They are able to take up DNA d) There is no specific guideline, all bacterial cells are always competent

c) They are able to take up DNA

What is a phenotype? a. the nucleous b. the Golgi Apparatus c. sequence of nucleotides in DNA d. a mutation

c. sequence of nucleotides in DNA

5-bomouracil resembles _________ and often base-pairs with ____________. a. guanine; cytosine b. thymine; adenine c. thymine; guanine d. adenine; cytosine

c. thymine; guanine

What is the Ames Test for? a. To identify bacteria b. to identify viable antibiotics c. to screen for carcinogens d. to identify a virus e. none of the above

c. to screen for carcinogens

What is true about mutations? a. they are the reason colonies are not identical b. single and two mutations are rare c. they give the population a chance to adapt to environments d. antibiotic resistant bacteria are examples of mutations e. all of the above

e. all of the above

Repair mechanisms that occur during DNA replication are: 1. mismatch repair 2. proofreading by DNA polymerase 3. light repair 4. SOS repair 5. excision repair A) 1,2 B) 2,3 C) 3,4 D) 4,5 E)1,5

A) 1,2

Carcinogens are ________. A) Cancer generating B) Healing C) Nutrients D) alkylating agents

A) Cancer generating

Which type of induced mutation increases the frequency of frameshift mutations? A) intercalating agent B) chemical that modifies a nucleobase C) base analog D) ultraviolet light

A) intercalating agent

Which mutation alters the DNA the most? A. Frameshift mutation B. Nonsense mutation C. Silent mutation D. Reversion

A. Frameshift mutation

What do transposons do? A. Inactivates the gene into which it inserts b. Activates the gene into which it inserts c. Does nothing d. Inactivates it momentarily and then activates it again

A. Inactivates the gene into which it inserts

Which biochemical mechanism is involved in both spontaneous and mutageninduced defect repair of DNA? A. Mis-paired nucleotide removed by DNA polymerase B. A protein will bind to the site of mismatch and cuts the unmyelinated strand C. Glycosylase removes the oxidized guanine D. The covalent bond between thymine molecules is broken

A. Mis-paired nucleotide removed by DNA polymerase

What two kinds of radiation are commonly used as mutagens? A. UV and X-rays B. UV and gamma C. Gamma and X-rays D. X-rays and infrared

A. UV and X-rays

What do intercalating agents do? A) Increase radiation B) Increase frequency of frameshift mutations C) Repair mutations D) Increase frequency of nonsense mutations

B) Increase frequency of frameshift mutations

Which of the following is NOT a mechanism of DNA transfer? A) Conjugation B) Recombination C) DNA-Mediated Transformation D) Transduction

B) Recombination

What is a last-effort attempt that bacteria use to repair extensively damaged DNA? A) mismatch repair B) SOS repair C) proofreading by DNA polymerase D) excision repair

B) SOS repair

Which of the following molecules functions as a "proofreader" for a newly replicated strand of DNA? a. DNA polymerase III b. primase c. helicase d. ligase

a. DNA polymerase III

What is the correct order for replica plating? A. Two agar plates on velvet, master plate onto sterile velvet, incubation B. Master plate into sterile velvet, two agar plates on velvet, incubation C. Incubation, master plate onto sterile velvet, two agar plates on velvet D. Master plate onto sterile velvet, incubation

B. Master plate into sterile velvet, two agar plates on velvet, incubation

What repair mechanism requires light? A) Thermoactivation B) Aeroreactivation C) Photoreactivation D) Chemoreactivation

C) Photoreactivation

The two types of transduction are__________. A) Mitosis and Meiosis B) Transpiration and conjugation C) Specialized and generalized D) Sterilization and asepsis

C) Specialized and generalized

What is an auxotroph? A) an organism that does not require growth factors B) a strain isolated from nature with a typical phenotype C) a mutant that requires a growth factor D) an organism that has undergone reversion

C) a mutant that requires a growth factor

What are two examples of metals that resistance plasmids encode resistance for? A) iron and mercury B) copper and arsenic C) mercury and arsenic D) copper and iron

C) mercury and arsenic

Ultraviolet light A) breaks the DNA strands B) created a stop codon C) produces thymine dimers D) increases the rate of replication and transcription

C) produces thymine dimers

Which of the following is the best description of a gene? A. A small molecule of DNA B. A single nucleotide C. A sequence of DNA nucleotides that codes for a single protein D. A sequence of amino acids in a protein

C. A sequence of DNA nucleotides that codes for a single protein

In what mechanism is DNA transferred during cell to cell contact? A) Replication B) Transduction C) Transformation D) Conjugation

D) Conjugation

What is transduction? A) "Naked" DNA is taken up from the environment by a bacterial cell B) DNA is transferred during cell-to-cell contact C) a specific physiological state that allows the cell to take up DNA D) DNA is transferred from one bacterial cell to another by a bacteriophage

D) DNA is transferred from one bacterial cell to another by a bacteriophage

What kind of cells do penicillin attack? A) only Gram-positive cells B) only Gram-Negative cells C) cells that are most sensitive to antimicrobial medications D) only growing cells

D) only growing cells

Which of the following is not a mechanism of horizontal gene transfer? A. DNA-mediated transformation B. Transduction C. Conjugation D. Homologous recombination

D. Homologous recombination

Chloroquine is a __________. A. Transposon B. Base analog C. Nucleobase D. Intercalating Agent

D. Intercalating Agent

What is the term for mutagens that increase the frequency of frame shift mutations? A. Alkylating agents B. Base analogs C. Tetragens D. Intercalating Agents

D. Intercalating Agents

What is true of plasmid transfer? A. It is sensitive to DNase addition B. Only part of the plasmid is transferred C. It does not require cell-to-cell contact D. It does require cell-to-cell contact

D. It does require cell-to-cell contact

Which of the following is not true concerning chromosome transfer? A. Cell to cell contact is required B. Only Hfr cells can be donors C. It is not sensitive to deoxyribonuclease addition D. The DNA is enclosed in a bacteriophage coat

D. The DNA is enclosed in a bacteriophage coat

What method is NOT used in horizontal gene transfer? A. DNA-mediated transformation B. Transduction C. Conjugation D. They are all used

D. They are all used

What is direct mutant selection? a. Cells inoculated onto medium that supports growth of mutant but not parent b. Isolates auxotroph from prototrophic parent stain c. The last-ditch repair mechanism d. Modified nucleobases that lead to base substitutions

a. Cells inoculated onto medium that supports growth of mutant but not parent

What is the most common type of mutation? a. Base substitution b. Deletion of nucleotides c. Addition of nucleotides d. Transposons

a. Base substitution

What is the main feature of Transduction? a. DNA is enclosed in a bacteriophage coat b. Naked DNA transferred c. cell-to-cell contact required d. None of the above

a. DNA is enclosed in a bacteriophage coat

What is the correct sequence of steps for plasmid transfer a) Making contact, Initiating transfer, Transferring DNA and Transfer complete b) Transferring DNA, Transfer Complete, Initiating Transfer and Making contact c) Making Contact, Initiating Transfer, Transfer Complete and Transferring DNA d) Transferring DNA, Initiating Transfer, Making contact and Transferring DNA

a) Making contact, Initiating transfer, Transferring DNA and Transfer complete

Which is NOT a possible mutation outcome of a base substitution? a) deletion b) nonsense c) silent d) missense

a) deletion

An agent that induces a mutation is known as a/an: a) mutagen b) agent c) analog d) excision

a) mutagen

A wild-type E. coli strain is a(n) a) phototroph b) auxotroph c) mutant d) induced mutant

a) phototroph

What is the repair mechanism when there is oxidized guanine in DNA? a. Action of glycosylase b. Mismatch repair c. Proofreading by DNA polymerase d. Photoreactivation (light repair)

a. Action of glycosylase

Chloroquine, an intercalating agent, has been used for many years to treat _________ a. Malaria b. Pneumonia c. Influenza d. Tuberculosis

a. Malaria

Which organism has has the trait of antibiotic synthesis? (reference: pg 225) a. Streptomyces sp. b. Bacillus anthracis c. Bacillus thuringiensis d. Rhizobium sp.

a. Streptomyces sp.

Which of the following has sensitivity to Deoxyribonuclease Addition (enzyme that degrades DNA)? (reference: pg 217) a. Transformation b. Transduction c. Plasmid Transfer d. Chromosome Transfer

a. Transformation

Penicillin enrichment is sometimes used before replica plating. a. True b. False

a. True

When a genetic change occurs in a single cell then passed to the offspring is known as ___. a. Vertical Gene transfer b. Mutation c. Horizontal gene transfer d. None of the above

a. Vertical Gene transfer

What is an auxotroph? a. a mutant that requires a growth factor b. DNA c. a mutant that doesn't need a growth factor d. nonsense mutation

a. a mutant that requires a growth factor

Base substitutions are more common when grown in: a. aerobic environments b. anaerobic environments c. both A and B d. none of the above.

a. aerobic environments

What is a phenotype? a. an organism's observable traits b. a sequence of nucleotides c. bacteria cells d. a "fit" organism e. changes in a genetic sequence

a. an organism's observable traits

What is the term for a mutant that requires a growth factor? a. axotroph b. prototroph c.wild-type organsim d. homologous mutant

a. axotroph

Which of the following statements is true? a. conjugation requires a sex plus extending from the surface of a cell. b. conjugation involves a C factor c. conjugation is an artificial genetic engineering technique d. conjugation involves DNA that has been released into the environment

a. conjugation requires a sex plus extending from the surface of a cell.

Which of the following agents causes an induced mutation that results in the addition or subtraction of nucleotides? a. intercalating agents b. base analogs c. alkylating agents d. transposon insertion

a. intercalating agents

Which of the following is NOT true of a vector? a. it is too big to manipulate in a laboratory b. it can survive inside a cell c. it contains a recognizable genetic marker d. it can ensure genetic expression

a. it is too big to manipulate in a laboratory

Which mechanism fixes errors missed by DNA polymerase? a. mismatch repair b. DNA ligase c. direct selection d. indirect selection

a. mismatch repair

What is the name of the mutation that causes a premature stop codon? a. nonsense b. frameshift c. point d. silent

a. nonsense

Which of the following mutations occur due to base substitution? a. silent mutation b. point mutation c. knockout mutation d. frameshift mutation

a. silent mutation

UV radiation can form which kind of dimers, causing distortion of the DNA double helix? a. thymine b. adenine c. guanine d. cytosine

a. thymine

A ___________ is able to change it's location within the genome. a. transposon b. enzyme c. growth factor d. alkylating agent

a. transposon

How is ultraviolet (UV) light mutagenic? a) It causes a strand break in DNA leading to improper base pairing repairs b) It creates dimers between adjacent thymine molecules within DNA leading to the inability of replication c) By inserting flat molecules between adjacent pairs in a strand of DNA d) UV light, while causing mutations, is not in fact mutagenic

b) It creates dimers between adjacent thymine molecules within DNA leading to the inability of replication

Which statement is true about Plasmids a) Most plasmids are single-stranded b) They do have an origin of replication, and can replicate independently of the chromosome before the cell divides c) They make the cell very unstable making it hard to survive in different environments d) Many bacterial plasmids are readily transferred by

b) They do have an origin of replication, and can replicate independently of the chromosome before the cell divides

What is horizontal gene transfer? a) passing of DNA from parent to daughter cells b) movement of DNA from one organism to another c) change in existing nucleotide sequence of cell's DNA d) change in 1 base pair

b) movement of DNA from one organism to another

The mutation rate of different genes usually varies between _______ and ________ per cell division a. 102; 1010 b. 10-4; 10-12 c. 10-2; 10-10 d. 104; 1012

b. 10-4; 10-12

How is screening for possible carcinogens conducted? a. penicillin enrichment b. Ames test c. replica plating d. direct selection

b. Ames test

Which enzyme has a proofreading capability? a. DNA Ligase b. DNA polymerase c. RNA polymerase d. Endonuclease

b. DNA polymerase

What kind of damage does UV light do to DNA? a. It creates a (covalent-bonded) thymine dimer that distorts the DNA and damages the DNA directly. b. It creates a (covalent-bonded) thymine dimer that distorts the DNA but does not damage the DNA. It is the SOS repair that damages the DNA when it repairs it in the event of mass scale damage c. It creates a (covalent-bonded) thymine dimer that distorts the DNA but does not damage the DNA. It is the SOS repair that damages the DNA when it repairs it in the event of even minor damage d. UV light damages DNA by denaturing it beyond

b. It creates a (covalent-bonded) thymine dimer that distorts the DNA but does not damage the DNA. It is the SOS repair that damages the DNA when it repairs it in the event of mass scale damage

Which type of mutation causes a change in a single base pair? a. Knockout mutation b. Point mutation c. Frameshift mutation d. Silent

b. Point mutation

A mutation that still codes for the same amino acid is? a. Missense mutation b. Silent mutation c. Nonsense mutation d. Frameshift mutation

b. Silent mutation

The function of a transposon is ____ a. Coding for genes which allow cell to occupy specific environmental locations b. To Move DNA to different locations in the same cell c. Coding for non-essential genetic information d. To move DNA to different bacterial cells

b. To Move DNA to different locations in the same cell

How are genes transferred between bacteria? a. DNA mediated transformation b. Transduction c. Conjugation d. All of the above

b. Transduction

What is the method of genetic recombination in which a mutation arises in a single cell and it then passed to progeny? a. Horizontal gene transfer b. Vertical gene transfer c. Lateral gene transfer d. Conjugation

b. Vertical gene transfer

Which type of radiation causes single and double strand breaks in DNA? a. Transposons b. X-Rays c. Ultraviolet (UV) light d. None of the above

b. X-Rays

What is the mechanism of DNA transfer that uses fertility plasmid and direct contact between the donor and recipient? a. transduction b. conjugation c. transformation d. competence

b. conjugation

Where would you find a collection of bacterial clones which contain a specific gene of an organism? a. allelic database b. gene library c. bacterial bank d. no such collection exists

b. gene library

When only one base pair is changed, the mutation is called: a. silent mutation b. point mutation c. missense mutation d. nonsense mutation

b. point mutation

Base substitution leads to three possible mutation outcomes a. frameshift mutation, missense mutation, nonsense mutation b. silent, missense or nonsense c. spontaneous mutation, missense or silent d. reversion, nonsense or frameshift

b. silent, missense or nonsense

Which type of radiation causes thymine dimers? a. x-rays b. ultraviolet c. infrared d. gamma rays

b. ultraviolet

Mismatch repair... a. mixes up base pairs and tries to put them back together like a puzzle b. fixes errors missed by the proofreading of DNA polymerase c. takes apart bases d. messes everything up

b. fixes errors missed by the proofreading of DNA polymerase

Mobile gene pool or mobliome can move from one DNA molecule to another, carried on mobile genetic elements including: a) various plasmids, transposons, R genes and resistance transfer factor (RTF). b) Genomic Islands, Phage DNA, R genes and Resistance transfer Factors. c) Various Plasmids, Transposons, Genomic Islands and Phage DNA. d) Insertion Sequence, Transposons, R genes and Genomic Islands

c) Various Plasmids, Transposons, Genomic Islands and Phage DNA.

An example of an alkylating agent is: a) 5-Bromouracil b) Ethidium bromide c) nitrosoguanidine d) Ultraviolet (UV) light

c) nitrosoguanidine

. It takes ______________ nucleotide pairs to be added/deleted to add/delete one codon. a. 1 b. 2 c. 3 d. 4

c. 3

5-bromouracil is an example of? a. A chemical that modifies nucleobases b. An intercalating agent c. A base analog d. None of the above

c. A base analog

What results from the intercalating agent, Ethidium bromide? a. Addition of nucleotides b. Subtraction of nucleotides c. Addition or subtraction of nucleotides d. Insertional

c. Addition or subtraction of nucleotides

Which of the following forms of DNA transfer between bacteria is the least common and involves Hfr cells? a. Conjugation b. Transduction c. Chromosomal DNA transfer d. Transformation

c. Chromosomal DNA transfer

What is the purpose of conjugation? a. "Naked" DNA is taken up from the environment by a bacterial cell b. DNA is transferred from one bacterial cell to another by a bacteriophage c. DNA is transferred during cell-to-cell contact d. DNA is transferred outside of the cell

c. DNA is transferred during cell-to-cell contact

What does the Ames test measure? a. cancer cell presence b. amount of RBCs in blood c. Effect of chemical on reversion rate of histidine-requiring Salmonella auxotroph d. amount of oxygen in specific areas of body

c. Effect of chemical on reversion rate of histidine-requiring Salmonella auxotroph

Which is not a method used to repair damage from UV light? A. Excision repair b. Photo reactivation c. Insertion sequence d. SOS repair

c. Insertion sequence

Which mechanism changes the existing nucleotide sequence of a cell's DNA a. Horizontal gene transfer b. Vertical gene transfer c. Mutation d. Selection

c. Mutation

Which of the following is NOT an example of Spontaneous Mutation? (reference: pages 206-208) a. Base Substitution b. Frameshift Mutation c. Radiation d. Transposons

c. Radiation

Base substitution leads to three possible outcomes, which is not a possible outcome? a. Nonsense mutation b. Missense mutation c. Sense mutation d. Silent mutation

c. Sense mutation

What type of mutation changes a nucleotide and results in a codon that codes for the same amino acid? a. Chromosomal inversion b. nonsense mutation c. Silent mutation d. missense mutation

c. Silent mutation

During replication, DNA polymerase ______ incorporates wrong nucleotide. a. Always b. Never c. Sometimes d. Usually

c. Sometimes

Which is NOT a step of PCR? a. Denaturation b. Priming c. Transcription d. Extension

c. Transcription

______ is sensitive to DNase addition while ________ is not. a. Chromosome transfer; Plasmid transfer b. Plasmid transfer; Chromosome transfer c. Transformation; Transduction d. Transduction; Transformation

c. Transformation; Transduction

How are thymine dimers produced? a. x-rays, causing breaks in DNA b. excessive Thymine bases in DNA c. UV light causes covalent bonds to form between adjacent thymine molecules on DNA strand d. none of the above

c. UV light causes covalent bonds to form between adjacent thymine molecules on DNA strand

Which of the following forms thymine dimers? a. X-Rays b. Chemotherapy c. Ultraviolet Radiation d. alcohol

c. Ultraviolet Radiation

Base substitutions caused by spontaneous mutations are more common in which kind of environment? a. anaerobic b. aquatic c. aerobic d. high temperature

c. aerobic

Carcinogens are... a. cancer killers b. cancer friends c. cancer-generating d. cancer enemies

c. cancer-generating

In a cell that lost a plasmid, what is its greatest disadvantage? a. cell will die if it loses its plasmid b. it can no longer replicate c. cell wont survive as well in particular environments d. There is no disadvantage to losing a plasmid

c. cell wont survive as well in particular environments

Although two cells are totally unrelated, one cell receives DNA from the other cell and incorporates this new DNA into its chromosome. This process is ______. a. crossing over of DNA from the two cells b. vertical gene transfer c. horizontal gene transfer d. transposition

c. horizontal gene transfer

____ is the transfer of the genetic material from one organism to another. a. mutation b. natural selection c. horizontal gene transfer d. vertical gene transfer

c. horizontal gene transfer

Which of the following methods of DNA repair involves enzymes that recognize and correct nucleotide errors in unmethylated strands of DNA? a. light repair of T dimers b. dark repair of P dimers c. mismatch repair d. SOS response

c. mismatch repair

What is a Genotype a. number of genes in an organisms DNA b. observable characteristics of an organism c. sequence of nucleotides in DNA d. genes only found in bacteria

c. sequence of nucleotides in DNA

What allows a cell to differentiate between the template and the new strand in the process of mismatch repair? a) It doesn't matter; either strand can be used in mismatch repair b) Proteins coded inside the template strand create a protective barrier surrounding the strand c) The new strand is immediately methylated which is detected by the repair enzyme d) The template strand undergoes methylation which is detected by the repair enzyme

d) The template strand undergoes methylation which is detected by the repair enzyme

The Ames test: a. uses direct selection b. if mutagenic, reverse rate increases relative to control c. uses indirect selection d. A & B e. A &

d. A & B

Examples of induced mutation are? a. Chemical mutagens b. Transposition c. Radiation d. All of the above

d. All of the above

What happens during transduction? A. Naked DNA uptake by bacteria b. DNA transfer during cell-to-cell contact c. Insertion into gene inactivating it d. Bacterial DNA transfer by viruses

d. Bacterial DNA transfer by viruses

Chemical mutagens may cause _____ substitutions or frameshift mutations. a. Acid b. Nucleotide c. Chemical d. Base

d. Base

What is the most common type of mutation? a. Induced mutation b. Transposons c. Frameshift mutation d. Base substitution

d. Base substitution

A mechanism involved in nucleotide repairs include: a. "proofreading" by DNA polymerase b. Mismatch repair c. Transposons d. Both A and B

d. Both A and B

What kind of mutations do chemical mutagens cause? A. Base substitutions b. Frameshift mutations c. Point mutations d. Both A and B

d. Both A and B

What are genomic islands? a. Codons b. RNA c. Energy source d. DNA segments.

d. DNA segments.

Compare Direct Selection to Indirect Selection. (reference: ch 8 powerpoint, slide 24) a. Direct Selection is a main approach, Indirect Selection is a minor approach b. Direct Selection is a minor approach, Indirect Selection is a main approach c. Direct Selection involves isolating auxotroph from phototropic parent strain, Indirect Selection involves cells inoculating onto medium that supports the growth of mutant but not parent d. Indirect Selection involves isolating auxotroph from phototropic parent strain, Direct Selection involves cells inoculating onto medium that supports the growth of mutant but not parent

d. Indirect Selection involves isolating auxotroph from phototropic parent strain, Direct Selection involves cells inoculating onto medium that supports the growth of mutant but not parent

What type of phage is a transduction fragment? a. It is a phage that is introduced into the host cell thereby infecting the host cell and eventually making the cell burst. b. It is a special phage that has pseudo-tail that is able to penetrate through the cytoplasm and inject its DNA directly into the bacterial cell's nucleus. c. It is a phage that is made during a rare event when part of the synthesizing phage's DNA breaks off and fuses to the protein capsule making the fragment that is extremely infectious. d. It is not a phage but a special type of DNA fragment that is made during a rare event when part of the synthesizing phage's DNA breaks off and fuses to the protein capsule making the fragment a "bacteriophage" that integrates with any given host cell's chromosome.

d. It is not a phage but a special type of DNA fragment that is made during a rare event when part of the synthesizing phage's DNA breaks off and fuses to the protein capsule making the fragment a "bacteriophage" that integrates with any given host cell's chromosome.

Which of the following is a method used to detect specific RNA molecules? a. Southern blot b. Western blot c. Eastern blot d. Northern blot

d. Northern blot

How does an enzyme repair an error in DNA? a. Proofreading by DNA Polymerase b. Mismatch repair c. Transposition d. Proofreading by DNA Polymerase AND Mismatch repair

d. Proofreading by DNA Polymerase AND Mismatch repair

Which type of repair is considered a last effort attempt when DNA is so heavily damaged from UV light? a. mismatch b. photoreactivation c. excision d. SOS

d. SOS

A mutation which a nucleotide change still yields the same amino acid is ____. a. Missense mutation b. Nonsense mutation c. Point mutation d. Silent Mutation

d. Silent Mutation

Before mutations can affect a population permanently, they must be _______. a. lasting b. inheritable c. beneficial d. all of the above

d. all of the above

Which of the following are base substitutions? a. silent mutation b. missense mutation c. nonsense mutation d. all of the above e. none of the above

d. all of the above

What happens if damaged DNA is not repaired? a. it can lead to cell death b. it can lead to cancer in animals c. it can lead to mutations rarely d. all the above are true

d. all the above are true

What are mutagens? a. a mutation in the genetic code b. a new allele in a population c. a change in a DNA base pair d. an agent that causes mutation

d. an agent that causes mutation

What actions does the DNA perform to ensure correct nucleotide sequencing? a. Proof reading b. UV rays c. mismatch repair d. correction e. Proofreading AND mismatch repair

e. Proofreading AND mismatch repair

What is true about horizontal gene transfer? a. it is the movement of DNA from one cell to another b. it can only be studied if the donor and recipient are genetically different c. it is responsible for the spread of Staphylococcus aureus d. it is not the same as vertical gene transfer e. all of the above

e. all of the above