Deck 11: DNA and Genes

Question 1

All cells in an organism contain a full copy of that organism's DNA.Your ears do NOT produce digestive enzymes because

A) stomach cells have extra DNA.
B) ear cells have nonfunctional DNA.
C) some DNA is deleted from cells where it is not needed.
D) different genes are expressed in different parts of an organism.

Answer 1

D

Question 2

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

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

Answer 2

C

Question 3

Before 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.

Answer 3

D

Question 4

The hereditary genetic material present in all living cells is

A) carbohydrate.
B) protein.
C) DNA.
D) RNA.

Question 5

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 6

What is NOT true of the five different cell types from the individual shown in the following figure?

A) They have the same DNA sequence.
B) They contain the same genes.
C) They express the same genes at the same time.
D) They have the same housekeeping genes.

Question 7

Assume a certain molecule of DNA is composed of exactly 22 percent adenine.How much cytosine would you expect to find in this molecule?

A) 22 percent
B) 28 percent
C) 44 percent
D) 56 percent

Question 8

Along one side of a DNA molecule,the nucleotides are connected to each other 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 9

This figure shows a short sequence of DNA.During DNA replication,the piece of DNA depicted below 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 10

Where in this diagram of the flow of genetic information of the cell would translation occur?

A) A
B) B
C) C
D) D

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

Once replication in a DNA molecule is complete,each new DNA molecule contains one old strand and one new strand.This type of replication is called

A) transcriptive.
B) semiconservative.
C) covalent.
D) corruptive.

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) variations in phenotypes.

Question 14

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

A) knowledge that chromosomes were composed of 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.

Question 15

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 16

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.

Question 17

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 As in one strand would be equal to the sum of the Cs and Gs 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 18

Which of the following is NOT a base found in DNA?

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

Question 19

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 20

Estrogen is a hormone that binds to a receptor on the surface of some cells.This binding causes regulatory molecules in the nucleus to interact with a segment of DNA that precedes some genes.This interaction activates the gene and causes gene expression.The segment of DNA that the regulatory molecules bind to is called a

A) promoter.
B) transcript.
C) chromosome.
D) nucleotide.

Question 21

Would you expect the presence of spacer DNA to increase or decrease the frequency of linkage between genes?

A) Decrease it, because the spacer DNA is removed from the genome before transcription.
B) Decrease it, because the spacer DNA increases the probability of crossing-over between genes.
C) Increase it, because the spacer DNA is tightly connected to the genes on both sides.
D) Increase it, because the spacer DNA encourages the insertion of transposons into the DNA.

Question 22

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 23

In plants,transposons are often the cause of variegation (the formation of white stripes of cells on a green leaf).Which of the following explains why a transposon might have this effect?

A) The white cells are dead cells. When a transposon moves from one chromosome to another, it kills its host cell.
B) When a bacterium infects a plant cell, the plant cell begins producing bacterial proteins rather than plant proteins.
C) When a transposon "jumps" into the gene involved in the production of the green pigment in a plant, the gene no longer functions so the cells are all white.
D) When a transposon enters a cell, it inhibits the translation of all proteins.

Question 24

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

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

Question 25

A segment of DNA is present in a gene,is transcribed,but is not used in translation.This segment of DNA is a(an)

A) intron.
B) transposon.
C) spacer DNA.
D) exon.

Question 26

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

A) Humans have the most efficient DNA repair proteins.
B) A mutation in the gene for a DNA repair protein may make mutations in other genes more common.
C) Certain proteins can repair damaged DNA.
D) The vast majority of DNA damage is fixed.

Question 27

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 28

Benzopyrene is a compound found in cigarettes that binds to the base guanine in DNA.This distorts the DNA double helix and causes changes in DNA sequence.Based on this information,benzopyrene is a

A) DNA repair protein.
B) histone.
C) transposon.
D) mutagen.

Question 29

The difference between the different 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 30

Most eukaryotic DNA is

A) single-stranded.
B) noncoding.
C) regulatory sequences.
D) prokaryotic.

Question 31

A rapidly dividing cell is exposed to a chemical that converts the bond that forms between adenine and thymine to a covalent bond.Which of the following is most likely to occur?

A) DNA replication would produce two molecules of DNA with mutations at every base that once held an A-T base pair.
B) DNA replication would not occur because the two nucleotide strands that make up the DNA molecule would not be able to separate.
C) DNA replication would occur more slowly because DNA repair proteins would have to fix the covalent bonds before replication could begin.
D) DNA replication would be faster because covalent bonds require less energy to break than hydrogen bonds.

Question 32

Which of the following does NOT correctly state a difference between prokaryotic and eukaryotic DNA organization?

A) Prokaryotic DNA groups genes with related functions together, whereas eukaryotic DNA does not.
B) Prokaryotic DNA has few noncoding regions, unlike eukaryotic DNA.
C) Eukaryotic DNA is usually arranged more simply than prokaryotic DNA.
D) Eukaryotic genomes contain more genes than prokaryotic genomes.

Question 33

A mistake during which of the following processes would have the most long-lasting effects on an organism and its offspring?

A) replication in germ line cells
B) transcription in somatic cells
C) translation in germ line cells
D) mitosis in somatic cells

Question 34

Mismatch errors are

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

Question 35

Assume a cell present in your body has performed a mismatch error during the process of DNA replication.This error has resulted in the generation of a new allele for one of your genes.For this new allele to be inherited by your offspring,which of the following conditions must be true?

A) The error must be repaired.
B) The error must be caused by a chemical mutagen.
C) The error must occur in the germ line cells.
D) The new allele produced must be dominant.

Question 36

The adenine bases in a DNA molecule are radioactively labeled.The DNA is then placed in a solution containing unlabeled nucleotides and the enzymes needed for DNA replication.The DNA molecule is allowed to replicate twice,forming four new DNA molecules.You would find the radioactively labeled adenine in

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

Question 37

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

A) DNA repair proteins identify damaged DNA.
B) The sequence of nucleotides in the damaged DNA sequence guides the synthesis of the correct DNA sequence.
C) DNA-eating enzymes within the nucleus destroy entire strands of damaged DNA.
D) The damaged DNA undergoes DNA replication one more time.

Question 38

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 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) UV light promotes photosynthesis in bacteria.

Question 40

Replication of DNA CANNOT 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

When the wrong base is inserted during DNA replication,a(n)________ error occurs.

Question 42

Housekeeping genes

A) prevent repressors from binding the promoter.
B) prevent operators from expressing genes.
C) are expressed by most of the cells in an organism.
D) break down a cell's DNA.

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

DNA ________ results in the copying of a DNA molecule.

Question 45

Why do chromosomes only reach their highest level of compaction during mitosis and meiosis?

A) to allow transcription of the most genes
B) to keep the chromosomes organized while they are being divided up
C) to allow the chromosomes to fit in the nucleus
D) to cover the histones that might interfere with division

Question 46

DNA consists of two twisted strands of ________.

Question 47

If their food source changes from lactose to arabinose,bacteria turn off their genes for lactose enzymes and turn on their genes for arabinose enzymes.Why don't bacteria express the genes for both lactose and arabinose enzymes all the time?

A) To prevent the waste of energy and resources on unneeded protein production.
B) Ribosomes will only transcribe one gene at a time in prokaryotes.
C) The unneeded proteins will bind to noncoding DNA and interfere with transcription.
D) The lactose and arabinose enzymes will destroy each other.

Question 48

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

Question 49

When compared,the nucleotide sequences of different individuals are________.

Question 50

Which of the following is NOT true? Organisms turn genes on and off

A) depending on the function of the cell.
B) in response to environmental changes.
C) to cause certain developmental changes.
D) to switch from prokaryotic to eukaryotic status.

Question 51

One parent is a carrier for a recessive disease.The other parent is not a carrier and does not have the disease.Is it necessary for the fetus to undergo prenatal genetic screening to determine if she has the disease?

A) Yes, the fetus may have inherited the disease from her carrier parent.
B) Yes, the disease may be dominant in the fetus.
C) No, the fetus may be a carrier but will not have the disease.
D) No, the fetus can neither be a carrier nor have the disease.

Question 52

How can a cell contain DNA molecules that are much longer than the cell?

A) The cell expands to fit the DNA inside.
B) DNA not used by that cell is deleted.
C) DNA is very narrow and tightly packed.
D) RNA copies allow DNA to dissolve.

Question 53

When Francis Collins described the Human Genome Database as a "shop manual," he meant that the human genome contains

A) information about how closely related we are to other organisms.
B) information about the probability of an individual developing a disease.
C) instructions for making mechanical objects.
D) instructions for making all the RNAs and proteins that make up a human.

Question 54

Which of the following might lead to a genome copy number variant in which the individual has only one copy of a gene instead of the normal two copies?

A) chromosomal translocation
B) chromosomal deletion
C) chromosomal inversion
D) base pair mismatch

Question 55

The following table shows which of these four genes are on or off in three different cell types. Why is the expression of the rRNA gene so different from the expression of the other genes in the table?

A) rRNA is required for the proper functioning of all cells, but the products of the other genes are only essential to the function of one cell type.
B) rRNA is easier to produce than the products of the other genes.
C) The rRNA gene is found in the genomes of all three cell types, but the other genes are only found in the genomes of their specific cell type.
D) rRNA is needed at all stages of the cell cycle, but the products of the other genes are only needed during cell division.

Question 56

When the breast cancer genes,BRCA1 and BRCA2,are mutated,damaged DNA in the cell is not corrected.Based on this information,the BRCA genes produce ________ proteins.

Question 57

To convert genetic information into a phenotype,the process labeled with the letter D in this diagram of the process of gene flow in a cell requires ________.

Question 58

One level of DNA packing involves the DNA being wound around

A) histone proteins.
B) an RNA molecule.
C) cytoplasmic organelles.
D) translation enzymes.

Question 59

Scientists discovered that Otzi,the 5,200-year-old frozen Copper Age man found in the Alps in 1991,had a variable DNA sequence called K.What caused the variations in this DNA sequence?

A) mutations
B) diet
C) injuries he sustained
D) his frozen condition

Question 60

The enzymes involved in ATP synthesis in the mitochondria are likely to be encoded by ________ genes.

A) regulatory
B) DNA repair
C) housekeeping
D) transposon

Question 61

The 220 different cell types in the human body each contain all of the same DNA found in every other cell type.

Question 62

A gene sequence is disrupted by a mobile segment of DNA such that the gene is no longer functional.The mobile segment of DNA is a ________.

Question 63

Borrelia burgdorferi has a genome of 0.5 million base pairs and little noncoding DNA.Borrelia burgdorferi is a ________.

Question 64

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

Question 65

Enzymes proofread base pairing during DNA replication.

Question 66

The genome of a prokaryote rarely contains ________ DNA sequences that do not undergo transcription.

Question 67

Protein is the hereditary genetic material in human cells.

Question 68

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

Question 69

In eukaryotes,some genes with related functions are found on different chromosomes.

Question 70

Translation builds DNA from an RNA template.

Question 71

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 72

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

Question 73

Mutations can lead to the formation of new alleles of a gene.

Question 74

A change in an organism's environment generally results in a change in ________,leading to the production of different types of proteins.

Question 75

In the following diagram of the bead-on-a-string level of DNA packaging,DNA is indicated by the letter A.

Question 76

________ DNA consists of stretches of nucleotides that separate genes.

Question 77

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

Question 78

The process of DNA replication is error free.

Question 79

DNA is ________ [more or less] tightly packaged during interphase when most gene expression occurs.

Question 80

DNA is tightly packed around protein spools known as ________.