Deck 14: Dna: the Genetic Material

Question 1

Which of the following statements about the Hershey-Chase experiment is false?

A)DNA was labeled with radioactive phosphorus.
B)Protein was labeled with radioactive sulfur.
C)The virus-infected bacteria showed radioactive phosphorus.
D)The virus-infected bacteria contained radioactive sulfur.

Answer 1

D

Question 2

As the two strands of DNA are unraveled,an enzyme relieves the strain on the two strands.The enzyme is

A)DNA polymerase.
B)DNA ligase.
C)DNA gyrase.
D)DNA endonuclease.
E)DNA exonucleasE.

Answer 2

C

Question 3

A bacteriophage typically attaches to the bacterium and then

A)converts the bacteria into immortal cells.
B)injects its nucleic acid into it,and then the ghost virus stays outside.
C)falls off every time.
D)viral protein is injected and the viral DNA stays outside.
E)it becomes inactivE.

Answer 3

B

Question 4

Which of the following is not a component of nucleic acids?

A)organic nitrogen bases
B)sugar
C)phosphate
D)protein

Question 5

___ is(are)the genetic material for all cellular organisms and some viruses.

A)RNA
B)DNA
C)Mitochondria
D)Chromosomes

Question 6

DNA consists of two antiparallel strands of nucleotide chains held together by

A)peptide bonds.
B)polar covalent bonds.
C)ionic bonds.
D)hydrogen bonds.
E)complementary base pairing bonds.

Question 7

___________ are viruses that attack bacteria.

A)Bacteriophages
B)HIV
C)Influenza
D)Common cold

Question 8

The enzyme that catalyzes the synthesis of new DNA molecules is called

A)DNA ligase.
B)DNA polymerase.
C)DNA gyrase.
D)DNA helicase.
E)DNA endonucleasE.

Question 9

The synthesis of the growing chain of DNA is carried out by adding nucleotides to the ___ end.

A)8'
B)3'
C)5'
D)1'

Question 10

Hershey-Chase concluded from their experiment with T2 bacteriophage that

A)proteins are the genetic material.
B)polysaccharide coat contains the genetic material.
C)DNA is the genetic material.
D)viruses are needed for DNA to function.
E)DNA contains sulfur.

Question 11

Nucleotides have phosphates attached at the ___ carbon atom of the sugar.

A)8'
B)3'
C)5'
D)1'

Question 12

Watson and Crick developed a model of DNA in which the two strands twist into the shape of a _________________.

A)circle
B)helix
C)double helix
D)double pleated sheet

Question 13

When nonvirulent bacteria were mixed with dead virulent bacteria,Griffith unexpectedly found that the injected mice died.He explained this behavior by suggesting the nonvirulent strain of bacteria as being

A)activated.
B)transformed.
C)translated.
D)transcribeD.
E)expressed.

Question 14

Griffith worked with

A)bacteriophage.
B)Drosophila.
C)frog eggs.
D)Streptococcus.

Question 15

The units of hereditary information is(are)called _____.

A)genes
B)DNA
C)RNA
D)chromosomes

Question 16

The method of DNA replication,where each original strand is used as a template to build a new strand,is called the

A)conservative method.
B)semiconservative method.
C)disruptive method.
D)continuous methoD.
E)replication and amplification method.

Question 17

DNA primase

A)creates a short RNA primer complementary to the RNA template.
B)creates a short DNA primer complementary to the RNA template.
C)creates a short DNA primer complementary to the DNA template.
D)creates a short template of an RNA primer that is complementary to the DNA primer.
E)creates a short RNA primer complementary to the DNA templatE.

Question 18

Avery and his coworkers showed the "transforming principle" as

A)protein.
B)polysaccharide.
C)DNA.
D)RNA.
E)lipid.

Question 19

Since both the strands of a DNA molecule are complimentary to each other,either one of the strands can be used as a _______ to reconstruct the other.

A)copy
B)basis
C)compass
D)template

Question 20

The reading of the bases along the length of a nucleic acid molecule for either transcription or translation is done from the

A)1' end.
B)2' end.
C)3' end.
D)4' enD.
E)5' end.

Question 21

Replication of DNA is

A)conservative.
B)redundant.
C)dispersive.
D)semiconservative.
E)semidispersivE.

Question 22

A scientist developed a procedure that would cause a particular chemical to bind with the nitrogen base adenine.If this chemical were applied prior to S in the cell cycle,what might be a logical prediction of the outcome?

A)The DNA replication would proceed except that all adenine would have the chemical bound to it and is incorporated into the new sister chromatids.
B)The DNA replication would proceed except that everywhere an adenine was supposed to be,a thymine was substituted into the new developing strand.
C)The DNA replication would proceed except cytosine and guanine would continue to form base pairs.
D)The DNA replication would stop because if adenine were bound then thymine would not have a complement with which to base pair.

Question 23

Which of the following choices is the correct sequence for DNA replication in

A)initiation,termination,elongation
B)initiation,elongation,termination
C)elongation,termination,initiation
D)elongation,initiation,termination
E)coli?

Question 24

DNA polymerase requires a(n)

A)amino acid primer.
B)lipid primer.
C)hydrophilic primer.
D)DNA primer.
E)RNA primer.

Question 25

Which of the following statements about replication of DNA is false?

A)The two strands are separated.
B)Each strand is used as a template for making a new duplex.
C)The synthesis on each strand is in the opposite direction.
D)The newly synthesized DNA is packaged into one nucleus,and the old DNA is packaged into another nucleus.

Question 26

The two strands in the DNA molecule contain nitrogen bases which are

A)identical.
B)parallel.
C)complementary.
D)the same in all species.
E)exact copies of the protein they makE.

Question 27

The chemical bonds that stabilize the complimentary nitrogen bases into a double helix are

A)nitrogen bonds.
B)hydrogen bonds.
C)hydrophobic bonds.
D)peptide bonds.
E)phosphodiester bonds.

Question 28

Which of the following DNA replicating enzymes is responsible for unwinding the double helix of DNA?

A)DNA primase
B)DNA polymerase I
C)DNA helicase
D)DNA gyrase
E)DNA ligase

Question 29

Fourteen percent of the DNA nucleotides from a certain organism contain T.What amounts of the other bases would you expect to be present in this particular DNA?

A)14 % A,0% C,36 % G
B)14 % A,36 % C,14 % G
C)14 % A,36 % C,36 % G
D)14 % T,38 % C,36 % G
E)14 % T,36 % C,36 % U

Question 30

If a short sequence of DNA is AATTGCCGT,its complement is

A)AAAACGCCA.
B)TTAACGGCT.
C)TTAACGGCA.
D)TTAAGCCGA.

Question 31

The double helix model was proposed by

A)Watson and Crick.
B)Griffith.
C)Avery.
D)Franklin.
E)Beadle and Tatum.

Question 32

The chemical bond connecting one nucleotide with the next one along the nucleic acid chain is called a

A)C = C bond.
B)hydrogen bond.
C)hydrophobic bond.
D)phosphodiester bonD.
E)peptide bond.

Question 33

The replisome has two main subcomponents.They are

A)the replication folk and the sliding clamp subunit.
B)the primosome and the sliding clamp subunit.
C)the replication folk and the DNA pol III enzymes.
D)the DNA pol III enzymes and the sliding clamp subunits.
E)the primosome and a complex of two DNA pol III enzymes.

Question 34

Replication always proceeds by adding new bases to the

A)1' end.
B)2' end.
C)3' end.
D)4' enD.
E)5' end.

Question 35

Information obtained by Franklin from X-ray crystallography on DNA suggested that it is a

A)helix.
B)ribbon.
C)hollow cylinder.
D)pleated sheet.
E)icosahedron.

Question 36

When DNA is replicated during S of the cell cycle,the sequence is maintained but the double strand is not.Each strand of the original double strand accompanies its new complement strand.This process is known as the

A)disruptive DNA replication.
B)conservative DNA replication.
C)semiconservative DNA replication.
D)dispersive DNA replication.
E)stabilizing DNA replication.

Question 37

The site of the opening of the DNA strands where active replication occurs is referred to as the

A)replication folk.
B)replisome.
C)primosome.
D)DNA pol III complex of two enzymes.
E)sliding clamp subunit.

Question 38

Griffith,a British microbiologist,used a bacteria and mice to demonstrate transformation.His results clearly offered evidence for that process.Transformation is

A)the ability for bacterial homologous chromosomes to transform themselves into an exact copy,sometimes referred to as DNA replication.
B)the ability of the nucleus of a cell to regenerate and repair itself when damaged by bacterial infections.
C)the ability of the infected mice to transform the bacteria from pathogenic to non-pathogenic during the experiments.
D)the ability to transfer genetic materials from one cell to another.
E)the ability for the nucleus of a bacterial cell to bypass the process of DNA replication by transforming into a spore during unsuitable environmental conditions.

Question 39

The lagging strand is replicated with stretches of Okazaki fragments and that is why its synthesis is considered to be

A)discontinuous.
B)continuous.
C)primed.
D)never stopping.
E)semiconservativE.

Question 40

In 1952,Hershey and Chase confirmed Avery's (1944)results that

A)proteins were the repositories for hereditary information.
B)DNA was the repository for hereditary information.
C)RNA was the repository for hereditary information.
D)proteins and DNA were the repositories for hereditary information.
E)transformation in bacterial cells induced changes in the host's somatic cells.

Question 41

Which of the following enzymes removes the primers used for DNA replication?

A)DNA pol I
B)DNA pol II
C)DNA pol III
D)DNA pol I,DNA pol II,and DNA pol III can all remove primers

Question 42

If the $\beta$ subunit of DNA pol III had a mutation that affected its sliding clamp configuration,which of the following would be most affected?

A)DNA unwinding
B)supercoiling
C)proper formation of the replication fork
D)processivity

Question 43

You are asked to give a classroom demonstration of DNA supercoiling.To do so,you take two different colored pieces of rubber tubing,twist them very tightly and excessively around each other and join the ends of the tubing appropriately.Next,you remove the supercoiling by breaking one strand and unwinding it.In this demonstration,the breaking and winding simulates the action of

A)exonucleases.
B)polymerases.
C)helicases.
D)topoisomerases.

Question 44

When injected into a bacterial cell by T2 virus particles,the material that specifies the new generation of viruses is DNA and not protein.

A)Hershey and Chase
B)Chargaff
C)Franklin
D)Watson and Crick

Question 45

DNA always contain amounts of the four bases,A,G,C,and T,characteristic of the species,but A = T and G = C,and purines equals pyrimidines.

A)Hershey and Chase
B)Chargaff
C)Franklin
D)Watson and Crick

Question 46

DNA pol III synthesizes the leading strand as a continuous strand.The lagging strands are synthesized in segments,called

A)parental DNA.
B)Chargaff's segments.
C)repeating primers.
D)replisomes.
E)Okazaki fragments.

Question 47

Deoxyribose has a "free arm," a carbon that is not a member of the pentose ring.To which direction does this "free arm" face?

A)in the same direction as which the coding strand is read
B)in the opposite direction from which the coding strand is read
C)toward the nitrogenous bases
D)toward the O in the five carbon ring

Question 48

Which of the following DNA sequences is complementary to 5' ATGGTCAGT 3'?

A)5' ATGGTCAGT 3'
B)5' TGACTGGTA 3'
C)5' TACCAGTCA 3'
D)5' ACTGACCAT 3'

Question 49

Endonucleases and exonucleases are enzymes that can remove nucleotides.An endonuclease _______ while an exonuclease ______________.

A)chews away at the 5' end of DNA;cuts DNA internally
B)chews away at a 3' end of DNA;cuts the 5' end of DNA
C)cuts DNA internally;chews away at the end of DNA
D)adds nucleotides internally to DNA;adds nucleotides on the 3' and 5' ends of DNA

Question 50

The processivity of a polymerase is a measure of how fast it can copy a DNA template.A polymerase with a high processivity has a high speed,while a polymerase with a low processivity has a slow speed.Given this information,how does processivity relate to the sensitivity and error rate of a polymerase?

A)high processivity = high sensitivity and high error rate
B)high processivity = high sensitivity and low error rate
C)high processivity = low sensitivity and high error rate
D)high processivity = low sensitivity and low error rate

Question 51

The structure of DNA is a double helix with two polynucleotide chains running in opposite directions and held together by hydrogen bonding between pairs of bases.

A)Hershey and Chase
B)Chargaff
C)Franklin
D)Watson and Crick

Question 52

In which of the following cells might you expect to find the highest level of telomerase?

A)muscle cells
B)oocytes
C)neurons
D)cells that replenish the lining of the gut

Question 53

The DNA double helix is similar to a twisted ladder.What makes up the sides holding the rungs together?

A)phosphate groups only
B)alternating units of phosphate groups and sugars
C)sugars only
D)purines and pyrimidines

Question 54

Avery,MacLeod,and McCarty's experiments revealed that the transforming principle had all of the following properties except

A)its activity was destroyed by treatment with proteases.
B)its activity was unaffected by RNA-digesting enzymes.
C)its activity was unaffected by lipid extraction.
D)its activity was destroyed by treatment with DNA endonucleases.

Question 55

In Griffith's transformation experiments,

A)mice infected with live R form caused pneumonia and death in the mice.
B)the R form transformed the S form into a virulent variety.
C)mice infected with heat-killed S form and live R form caused pneumonia and death in the mice.
D)the S form lacked an enzyme involved in the manufacture of the polysaccharide coat,leading to the abnormally smooth colonies.

Question 56

Why does DNA pol I carry the number one when it is not the polymerase responsible for the bulk of DNA synthesis?

A)DNA pol I was the first polymerase isolated from
B)DNA pol I is the first polymerase to be activated during DNA replication.
C)DNA pol I is the only polymerase that has both 3' to 5' and 5' to 3' exonuclease activity.
D)DNA pol I is the smallest polymerase.
E)coli.

Question 57

Why is it essential for the nitrogenous bases to remain in one tautomeric form when part of a DNA molecule?

A)It allows the width between the phosphate strands to remain consistent.
B)It is essential for proper base pairing of A with T and C with G.
C)The presence of additional tautomeric forms would violate Chargaff's rules.
D)The presence of additional tautomeric forms would cause the two DNA strands to form a parallel configuration rather than an antiparallel configuration.

Question 58

X-ray crystallography of purified DNA fibers shows a pattern that suggests a helical structure,and provides dimensions of that structure.

A)Hershey and Chase
B)Chargaff
C)Franklin
D)Watson and Crick

Question 59

You are asked to participate in a clinical trial for a new drug that can activate telomerase.Which of the following is a likely risk of such a drug?

A)decreased capacity for tissue repair
B)increased vulnerability to cancer
C)premature aging
D)decreased telomere length

Question 60

Eukaryotic organisms solve the problem of time constraints on replication of DNA by

A)elimination of the initiation phase,thus shorten the length of the replication process.
B)producing several sliding clamp complexes that allow DNA pol III enzymes more binding sites.
C)allowing DNA gyrase to unravel the double helix faster than the DNA helicase,which then speeds up the formation of the replication folk.
D)using multiple origins of the replication on each chromosome,which results in multiple replicons.

Question 61

What would be the effect on DNA replication if the helicase was unable to hydrolyze ATP?

A)Helicases use the energy of ATP hydrolysis to unwind the strands of DNA during replication.Although,some DNA polymerases can unwind DNA as they synthesize new DNA,helicases make the process is much more efficient.If helicases cannot hydrolyze ATP,they cannot properly unwind the DNA,and replication would be slowed.
B)Helicases use the energy of ATP hydrolysis to wind the strands of DNA during replication.Although,some DNA polymerases can wind DNA as they synthesize new DNA,helicases make the process is much more efficient.If helicases cannot hydrolyze ATP,they cannot properly wind the DNA,and replication would be slowed.
C)Helicases unwind the strands of DNA during replication.If helicases cannot hydrolyze ATP,they cannot unwind the DNA,and replication would be stopped.

Question 62

After a long week of sunbathing on the beach,what type of DNA damage might you be concerned about?

A)photolyase-induced mutations
B)decreased telomere length
C)thymine dimers
D)uvr A,B,and C

Question 63

Xeroderma Pigmentosum (XP)is a rare autosomal recessive disorder.Patients with XP exhibit a cellular hypersensitivity to ultraviolet (UV)radiation,a high incidence of skin cancer and premature aging.Based on these clinical characteristics,what is the underlying cause for this disease?

A)defects in DNA repair
B)defects in DNA replication
C)lack of telomerase activity
D)shortened telomeres

Question 64

If an

A)Repair would take place through replication and recombination during sister chromatid paring.
B)Inaccurate replication of the genome would eventually result in cell death.
C)uvr B or C would handle the repair of the thymine dimer.
D)It would have no lasting effects.
E)coli strain were phr (no photoreactivation),uvrA (no excision repair),and recA (no SOS repair),what do you expect would be the result of thymine dimer formation?