Deck 12: DNA

Question 1

The order of the base pairs in a DNA molecule

A) differs from species to species.
B) is identical in all organisms.
C) is identical in organisms of the same species.
D) differs from cell to cell in a given organism.

Answer 1

A

Question 2

Why was the bacterial virus that Hershey and Chase used a good experimental system for determining whether DNA or protein was the molecule of inheritance?

A) The virus only contained DNA and protein and it was already known that the virus only injected its inheritable material into the cells it infected.
B) The DNA portion of the virus that Hershey and Chase used was known to be naturally radioactive, but the protein portion was not radioactive.
C) Viruses only reproduce outside of cells so it is easy to isolate their molecule of inheritance.
D) The DNA of viruses has a different, easier to visualize, structure than the DNA of humans.

Answer 2

A

Question 3

The early hypothesis that protein was the genetic material was based in part on the

A) knowledge that chromosomes were composed of both DNA and protein.
B) fact that proteins are small molecules and therefore easily copied.
C) fact that protein molecules are large and could carry a lot of information.
D) the idea that DNA molecules varied too much within cells of the same organism.

Answer 3

C

Question 4

The two strands of a DNA molecule are held together by _____ bonds between their base pairs

A) hydrogen
B) amino acid
C) phosphate
D) protein

Question 5

The hereditary genetic material present in all living cells is

A) strain S.
B) protein.
C) DNA.
D) RNA.

Question 6

The Hershey-Chase experiment with viruses led to the conclusion that DNA is the material of inheritance by showing that

A) the virus injects only DNA into bacteria.
B) the protein surrounding the bacteria is made of nucleic acids.
C) viruses are unable to infect bacteria without DNA.
D) radioactive phosphorus killed the bacteria but radioactive sulfur did not.

Question 7

In Griffith's experiments, transformation occurred when a small piece of

A) protein from the harmful strain of bacteria caused a mutation in the harmless strain.
B) DNA from the harmful strain of bacteria changed the characteristics of the harmless strain.
C) protein from the harmless strain of bacteria caused a mutation in the harmful strain.
D) DNA from the harmless strain of bacteria caused a mutation in the harmful strain.

Question 8

The evidence that one strain of bacteria can often transform another strain suggests that bacteria

A) are able to change into viruses.
B) must have protein as their hereditary material.
C) might be able to exchange pieces of DNA encoding antibiotic resistance.
D) must have single-stranded DNA in order to undergo transformation.

Question 9

The difference between alleles of a gene is

A) their DNA base sequences.
B) the way they are copied when the cell divides.
C) the type of lipid they are composed of.
D) not heritable.

Question 10

The figure below illustrates an experiment.
Why does the mouse shown in this experiment die?

A) The strain R bacteria were damaged by mutagens produced during the heating of the strain R bacteria.
B) The strain R bacteria were transformed with DNA from the strain S bacteria.
C) The mouse was infected with strain S bacteria before the experiment began.
D) The material of inheritance in the strain R bacteria was destroyed by heat allowing the strain R bacteria to take over.

Question 11

If one strand of DNA has the sequence CGATT, the sequence of the other strand of the same molecule will be

A) CGATT.
B) GCTUU.
C) TACGG.
D) GCTAA.

Question 12

When a cell divides, it

A) breaks down its DNA.
B) deletes old genetic information.
C) copies information from neighboring cells.
D) copies its own genetic information.

Question 13

The sequence of DNA differs among individuals within a species. This is the basis for

A) mutation.
B) protein structure.
C) base pairing.
D) inherited variation.

Question 14

Which of the following is not a base used during DNA synthesis?

A) thymine
B) adenine
C) guanine
D) uracil

Question 15

Along one side of a DNA molecule, the nucleotides are connected by

A) covalent bonds between phosphate groups and sugar molecules.
B) hydrogen bonds between adenine and guanine.
C) covalent bonds between bases and sugar molecules.
D) hydrogen bonds between adjacent sugar molecules.

Question 16

What part of a nucleotide accounts for the genetic variation between individuals?

A) sugar
B) phosphate
C) base
D) polymerase

Question 17

In Griffith's experiments, the genetic material was not destroyed in bacteria killed by heat. This suggested that

A) some combination of protein and DNA was the genetic material.
B) protein and DNA contained different amounts of genetic information.
C) DNA, not protein, might be the genetic material.
D) heat did not destroy the genetic information in proteins.

Question 18

The experiments conducted by Hershey and Chase were able to show that DNA was the genetic substance, because

A) both proteins and DNA in the viruses that they used contained radioactive sulfur.
B) only radioactive phosphorus was found inside of infected bacteria.
C) only radioactive sulfur was found inside of infected bacteria.
D) both proteins and DNA in the viruses that they used contained radioactive phosphorus.

Question 19

Frederick Griffith's experiments with mice showed that

A) infecting them with a harmless strain of bacteria killed the mice.
B) the hereditary material of heat-killed bacteria was destroyed.
C) living bacteria could incorporate hereditary material from killed bacteria.
D) the mice became resistant to the deadly bacteria.

Question 20

Which of the following would not be a required biological property of genetic material?

A) It must be variable.
B) It must exist in paired copies.
C) It must be able to be copied accurately.
D) It must contain the information needed for life.

Question 21

Why are high levels of radiation fatal to humans?

A) Radiation leads to permanent increases in the activity of DNA repair proteins.
B) Radioactive atoms act as mutagens.
C) Radiation increases the rate of DNA replication.
D) Radiation inhibits cell division so that dead cells cannot be replaced.

Question 22

Damaged DNA may be repaired by a special class of

A) nucleotides.
B) proteins.
C) deoxyribose molecules.
D) phosphate bonds.

Question 23

Is a species that lacks DNA repair mechanisms likely to have more or fewer variations between individuals than a species that possesses repair mechanisms?

A) Fewer, because there are fewer ways to change the DNA.
B) Fewer, because the repair mechanisms introduce more variation into the DNA sequence.
C) More, because more spontaneous mutations will go uncorrected.
D) More, because without a repair mechanism, the cell's tumor suppressor genes are inactivated.

Question 24

The figure below shows a short sequence of DNA.
During DNA replication, the piece of DNA depicted above will produce

A) one single-stranded molecule with the sequence CTAT.
B) two single-stranded molecules with the sequence GATA
C) one single-stranded molecule with the sequence CTAT and a separate single-stranded molecule with the sequence GATA.
D) two double-stranded molecules that look just like the image above.

Question 25

The figure below illustrates DNA undergoing replication.
The region indicated by the arrow in this image represents a

A) single base pair.
B) mismatch error.
C) mutation.
D) transformation.

Question 26

DNA replication

A) involves the copying of only the parts of a chromosome that encode protein.
B) occurs during S phase in the cell cycle.
C) in constantly occurring in all the cells in your body.
D) converts the double helix to a two single helices.

Question 27

The adenine bases in a DNA molecule are radioactively labeled. Once this DNA molecule had replicated twice to form four new DNA molecules with no other labeled adenine bases present, you would find the labeled adenine

A) in each of the eight strands.
B) in two of the eight strands.
C) in all but one strand.
D) in six of the eight strands.

Question 28

When examining the two complementary strands of nucleotides in one DNA molecule, you would expect to find that

A) the sum of Gs and Cs in one strand would be equal to the sum of the Gs and Cs in the other strand.
B) the sum of Ts and Gs in one strand would be equal to the sum of Cs and As in the other strand.
C) the sum of Ts and As in one strand would be greater than the sum of the Ts and As in the other strand.
D) the sum of As and Cs in one strand would be less than the sum of the Ts and Gs in the other strand.

Question 29

_______ is the change in the genotype of a cell that occurs after exposure to the DNA of another genotype.

Question 30

Once replication in a DNA molecule is complete, each new DNA molecule contains

A) one old strand and one new strand.
B) the paired old strands and the paired new strands.
C) new DNA polymerase.
D) a new sequence of nucleotides.

Question 31

The significance of specific base pairing in DNA is that

A) it stabilizes the sugar molecule.
B) it provides a method for making exact copies of DNA.
C) it prevents errors in DNA replication.
D) protein copies can be made directly from the DNA.

Question 32

Which of the following must occur for a mismatch error to be repaired?

A) Damaged DNA must be identified by DNA repair proteins.
B) The sequence of nucleotides in the damaged DNA sequence must guide the synthesis of the correct DNA sequence
C) Entire strands of damaged DNA must be destroyed by DNA-eating enzymes within the nucleus.
D) The damaged DNA must undergo DNA replication one more time.

Question 33

Which of the following will not generally cause mutations?

A) chemicals
B) radiation
C) mechanical forces
D) DNA replication

Question 34

To start DNA replication, the bonds holding the strands together are broken, and the molecule begins to unwind. Which of the following statements best summarizes what happens next?

A) New strands are synthesized and paired with each other.
B) Each old strand acts as a template for a new strand.
C) Each old strand is broken down into nucleotides.
D) Transformation results in a new DNA molecule.

Question 35

DNA is often damaged or may be replicated incorrectly. Which of the following is not true?

A) Humans do not have repair proteins.
B) Heat energy can damage DNA.
C) DNA can be repaired by proteins.
D) The vast majority of DNA damage is fixed.

Question 36

Which of the following is true?

A) The two strands of a DNA molecule are held together by covalent bonds.
B) A single strand within a DNA molecule is held together by hydrogen bonds.
C) The bases on one strand of DNA are held to the bases on the other strand by hydrogen bonds.
D) Hydrogen bonding between complementary base pairs causes the DNA molecule to twist into a spiral.

Question 37

Mismatch errors are

A) almost always corrected by mutagens.
B) caused by DNA polymerase.
C) almost always corrected by specialized proteins.
D) usually caused by mutated proteins.

Question 38

Children may be more susceptible to mutagens because

A) of the higher rates of cell division occurring in their bodies.
B) their organs, including the liver, are not fully mature and cannot efficiently remove toxins from the body.
C) a child's diet is normally higher in fat and many mutagens are soluble in fat.
D) all of the above

Question 39

Bacterial cultures are sometimes exposed to ultraviolet (UV) light in order to generate organisms with new genetic traits. Why do microbiologists choose to use UV light for this purpose?

A) UV light makes all cells antibiotic-resistant.
B) UV light has the ability to cause changes in DNA.
C) UV light is the usual source of energy for bacteria, thus giving them more energy for evolution.
D) none of the above

Question 40

Replication of DNA can't begin until

A) phosphate bonds between nucleotides are broken.
B) hydrogen bonds between complementary bases are broken.
C) covalent bonds between sugar molecules are broken.
D) hydrogen bonds between nucleotides in one strand are broken.

Question 41

Transformation builds DNA from an RNA template.

Question 42

Protein is the hereditary genetic material in human cells.

Question 43

During DNA replication the enzyme ___________ _____________ builds a new strand of DNA while using the old strand of DNA as a template

Question 44

During replication each "old" DNA strand serves as a template for a new strand.

Question 45

The "rungs" in the DNA "ladder" consist of _______ pairs.

Question 46

During DNA replication, the template strands of the original DNA molecule are complementary both to each other and to one of the new strands.

Question 47

People with xeroderma pigmentosum frequently exhibit skin cancer.The disease is a result of a mutation in a gene that produces a ______ ______ protein. Without this protein, cells cannot reverse the damage caused by exposure to ultraviolet (UV) light.

Question 48

The process of DNA replication is error-free.

Question 49

The sequence of bases along a single strand of DNA is complementary.

Question 50

Griffith's experiments proved that DNA was the genetic material.

Question 51

The experiments of Hershey and Chase showed that viruses contain DNA.

Question 52

To repair DNA, a protein cuts out the damaged section.

Question 53

DNA ____________ results in the duplication of a DNA molecule.

Question 54

A change in the DNA base sequence due to an uncorrected mismatch error is called a _______.

Question 55

The backbone of a DNA molecule is made up of sugars and _______.

Question 56

Labeling the _________ of a bacterial virus with radioactive phosphate allowed Hershey and Chase to determine whether DNA or protein was the molecule of inheritance.

Question 57

Exposure to ________________ light can cause sunburn and massive DNA damage to skin cells.

Question 58

When compared, the nucleotide sequences of different individuals are_______________.

Question 59

DNA consists of two twisted strands of _______.

Question 60

A _______ error occurs when the wrong base is inserted during DNA replication.

Question 61

The DNA of a rapidly dividing cell is exposed to a chemical known to convert the bond between adenine and thymine to a covalent bond. What would happen to the DNA replication in this cell? Explain your answer.

Question 62

Enzymes proofread base-pairing during DNA replication.