Deck 7: Dna Structure and Gene Function

Question 1

A DNA sequence that signals the start of a gene is

A)a codon.
B)an anticodon.
C)a terminator.
D)a promoter.
E)an amino acid attachment sitE.

Answer 1

D
Explanation: The promoter is like the cover of a book,showing the cellular machinery that a gene is present and where to start copying it.Please see section 7.3 for more information.

Question 2

A tRNA molecule is "bilingual" because it binds to

A)amino acids and DNA.
B)DNA and mRNA codons.
C)promoters and amino acids.
D)codons of mRNA and amino acids.
E)promoters and terminators.

Answer 2

D
Explanation: RNA and proteins are two different chemical languages which meeting in the tRNA.Please see section 7.4 for more information.

Question 3

DNA differs from RNA because,unlike RNA,

A)DNA contains uracil.
B)DNA contains thymine.
C)DNA can catalyze some chemical reactions.
D)DNA is single-strandeD.
E)DNA contains ribosE.

Answer 3

B
Explanation: DNA and RNA have different chemical letters in their languages.Please see section 7.2 for more information.

Question 4

The double helix of DNA is composed of building blocks called

A)amino acids.
B)monosaccharides.
C)phospholipids.
D)disaccharides.
E)nucleotides.

Question 5

RNA differs from DNA in many ways,including

A)DNA contains deoxyribose and RNA contains ribose.
B)DNA contains thymine and RNA contains uracil instead of thymine.
C)All answers are correct.
D)DNA is double stranded and RNA is single strandeD.
E)RNA can catalyze some chemical reactions and DNA cannot.

Question 6

A three-base sequence (loop)in tRNA that is complementary to a three-base sequence in mRNA is

A)a codon.
B)an anticodon.
C)a promoter.
D)a terminator.
E)an amino acid attachment sitE.

Question 7

What type of RNA carries the information that specifies a protein?

A)transfer RNA
B)ribosomal RNA
C)messenger RNA
D)double-stranded RNA
E)complementary RNA

Question 8

The "Central Dogma" of molecular biology described by Watson and Crick describes

A)the passing of genetic information from DNA to RNA by translation.
B)the passing of genetic information from RNA to protein by transcription.
C)the inheritance of traits between generations.
D)the production of energy in a cell.
E)the directional flow of genetic information in cells.

Question 9

In eukaryotic cells,sequences of mRNA removed before translation are called

A)introns.
B)anticodons.
C)exons.
D)rRNA.
E)terminators.

Question 10

What are proteins that initiate transcription in eukaryotes by recognizing sequences within the promoter region of a gene and attracting RNA polymerase?

A)repressors
B)inducers
C)transcription factors
D)TATA boxes
E)poly A tails

Question 11

The step of translation in which amino acids are added to the growing polypeptide is

A)mitosis.
B)initiation.
C)elongation.
D)termination.
E)transcription.

Question 12

Initiation,elongation,and termination are the three main steps in

A)translation only.
B)transcription and translation.
C)transcription only.
D)photosynthesis.

Question 13

The rungs of the DNA ladder are formed by base pairs

A)joined by covalent bonds.
B)joined by hydrogen bonds.
C)joined by ionic bonds.
D)NOT joined to each other.

Question 14

In the lac operon,the protein that binds to the operator to prevent transcription is

A)the repressor.
B)RNA polymerase.
C)DNA polymerase.
D)the promoter.
E)lactosE.

Question 15

What type of RNA carries amino acids to the ribosome?

A)complementary RNA
B)messenger RNA
C)ribosomal RNA
D)double-stranded RNA
E)transfer RNA

Question 16

In DNA molecules,

A)cytosine pairs with adenine.
B)thymine pairs with uracil.
C)adenine pairs with uracil.
D)adenine pairs with thymine.
E)cytosine pairs with thyminE.

Question 17

What process converts the mRNA "message" into a sequence of amino acids?

A)transcription
B)replication
C)mitosis
D)amino acid synthesis
E)translation

Question 18

The step of translation in which an mRNA,a small ribosomal subunit,and the initiator tRNA are aligned together is

A)initiation.
B)mitosis.
C)elongation.
D)termination.
E)transcription.

Question 19

A group of genes,a promoter,and an operator that control transcription are called a(n)

A)translational unit.
B)chromosome.
C)ribosome.
D)envelope.
E)operon.

Question 20

In DNA molecules,

A)cytosine pairs with guanine.
B)thymine pairs with uracil.
C)adenine pairs with uracil.
D)adenine pairs with guanine.
E)cytosine pairs with thyminE.

Question 21

How many codons are in the mRNA sequence GGAAUGAAACAGGAACCC?

A)12
B)6
C)27
D)9
E)3

Question 22

Mutations can be caused by environmental chemicals.

Question 23

Why would it take more energy to separate DNA with the sequence GCGCGCGC and its complementary strand than the sequence ATATATAT and its complementary strand?

A)A's and T's do not form pairs between separate DNA strands.
B)The helix is wound more tightly in G and C base pairs.
C)G and C base pairs form more hydrogen bonds between DNA strands.
D)The sequence containing G's and C's is longer.
E)G and C base pairs form more covalent bonds between DNA strands.

Question 24

If the DNA in a cell consists of 20% adenine,then it will also contain ___ guanine.

A)20%
B)80%
C)30%
D)40%
E)10%

Question 25

If the DNA in a cell consists of 20% adenine,it will also have _____ thymine.

A)30%
B)80%
C)40%
D)20%
E)10%

Question 26

The DNA sequence ATGCATGC will pair with which of the following DNA strands? 0_30_2012

A)TACGTACG
B)TACCTACC
C)ATGCATGC
D)TTGCATCC
E)CGTACGTA

Question 27

The length of a DNA sequence is _____ than the mature mRNA transcribed from it,because

A)shorter;it does not contain exons.
B)equal;it was transcribed from the DNA sequence.
C)longer;it does not contain introns.
D)shorter;each codon of three bases encodes only one amino aciD.
E)longer;each codon of one amino acid encodes three bases.

Question 28

Mutations can be caused by radiation.

Question 29

If you were seeking to change your life to avoid mutations in your DNA,which would be least useful to avoid?

A)errors in DNA replication
B)errors during meiosis
C)exposure to radiation
D)exposure to tobacco
E)exposure to magnesium

Question 30

"Mad cow disease" is caused by a viroid.

Question 31

Changes in gene expression can be adaptive,helping organisms contribute more to the next generation.

Question 32

The DNA sequence ATGCATGC will pair with which of the following RNA strands?

A)UACGUACG
B)CGAUCGAU
C)AUGCAUGC
D)TAGCTAGC
E)UAGCTAGC

Question 33

Mutations can be caused by errors in copying DNA.

Question 34

A change in a cell's DNA sequence is

A)replication.
B)transcription.
C)a mutation.
D)translation.
E)an operon.

Question 35

Only one of the two strands of DNA is transcribed because

A)RNA polymerase binds to the promoter,initiating transcription on only one strand of DNA.
B)the start of transcription is random along the chromosome and does not always occur on a gene.
C)RNA polymerase binds to the terminator,stopping transcription on one strand of DNA.
D)both strands are transcribed,but only one strand of DNA contains a reading frame.
E)DNA consists of only one strand in the nucleus of the cell.

Question 36

"Tomato bunchy top" is caused by a virus.

Question 37

In a "frameshift" mutation

A)the codon that mutates causes no change in the amino acid specified.
B)the codon that mutates causes a stop codon to occur instead of the placement of an amino acid.
C)the mutation does not occur in a codon.
D)the mutation is caused by an addition or deletion of one or more nucleotides.
E)the mutation is not in DNA.

Question 38

In a "silent" mutation

A)the codon that mutates causes a change in the amino acid specified.
B)the codon that mutates does not cause a change in the amino acid specified.
C)the codon that mutates causes a stop codon to occur instead of the placement of an amino acid.
D)the mutation does not occur in a codon.
E)the mutation is not in DNA.

Question 39

The amino acid that starts every protein and that is encoded by ACG is methionine.

Question 40

Using the genetic code,predict what type of mutation has occurred in the hemoglobin sickle cell anemia allele.
Normal allele GGAAUGAAACAGGAACCC
Mutant allele GGAAUGAAACAGGUACCC

A)a point mutation,Val to Glu
B)a frame shift
C)addition of a new stop codon
D)a point mutation,Glu to Val

Question 41

What did scientists discover was the primary cause for genetically controlled language disorder connected to language ability in other species?

A)The cause was one mutation in a single gene on one chromosome.
B)The disorder was not inherited but related to diet.
C)Affected family members were lacking vocal chords.
D)The cause was multiple mutations in multiple genes on one chromosome.
E)The cause was multiple mutations in multiple genes on many chromosomes.

Question 42

In the bacterium E.coli,a repressor protein binds to the operator region of the DNA in the absence of lactose,thus preventing the transcription of the genes of the lactose operon.

Question 43

In eukaryotes,transcription copies only one gene from one DNA strand of the chromosome.

Question 44

Most viruses

A)infect only a few closely related species.
B)infect only animal cells.
C)infect a wide variety of organisms.
D)cannot infect living cells.
E)infect only plant cells.

Question 45

Mutations cause incorrect sequencing of nucleic acids.Incorrect sequencing of DNA will result in new alleles,and it may lead to evolution.Incorrect sequencing of mRNA will result in a faulty protein,but it will not lead to evolution.

Question 46

If you were looking at an electron micrograph of an mRNA molecule being translated by many ribosomes at once,you would be looking at a picture from a prokaryote.

Question 47

A gene is any DNA sequence that is transcribed to any type of RNA.

Question 48

If one strand of DNA has the nitrogenous base sequence ATTCGACGCTA,then the complementary strand has the nitrogenous base sequence

A)TAAGCTGCGAT.
B)ATCGCAGCTTA.
C)UAAGCUGCGAU.
D)ATTCGACGCTA.

Question 49

Cystic fibrosis may be caused by a protein that does not fold correctly.

Question 50

What type of mutation occurred in the following?
Normal allele GGAAUGAAACAGGAACCC
Mutant allele GGAAUGAAACAGGUACCC

A)substitution
B)insertion
C)deletion
D)frameshift
E)No answer is correct.

Question 51

What type of mutation occurred in the following?
Normal allele GGAAUGAAACAGGAACCC
Mutant allele GGAAUGAAAUCAGGAACCC

A)insertion
B)substitution
C)deletion
D)frameshift

Question 52

Amanatin is a toxin found in the death cap mushroom,Amanita phalloides.It inhibits RNA polymerase,thus blocking

A)transcription.
B)translation.
C)replication.
D)cell division.
E)RNA splicing.

Question 53

A gene is an RNA sequence that is transcribed to mRNA only.

Question 54

if you were creating a system for protein synthesis in a test tube,for RNA you would only need tRNA and rRNA.

Question 55

In studies of the genetic basis of language,FOXP2 sequences differed the most between mice and

A)rhesus monkeys.
B)gorillas.
C)chimpanzees.
D)humans.
E)All answers are correct.

Question 56

If you found a living Neadertal,genetic analysis of FOXP2 would show maximal similarity to the homologous gene in mice.

Question 57

What role do hydrogen bonds play in the DNA molecule?

A)Hydrogen bonds link complementary nitrogenous bases,thus keeping the two strands of DNA parallel to each other.
B)Hydrogen bonds link the two strands of DNA end to end during transcription and translation.
C)Hydrogen bonds link the two strands of DNA end to end during transcription only.
D)Hydrogen bonds link the complementary deoxyribose sugars,thus maintaining a separation between the two DNA strands.
E)No answer is correct.

Question 58

A poly A tail is added to the mature mRNA after transcription.

Question 59

Using the genetic code,what is the sequence of amino acids represented by the codons AUGUCAACGUGA?

A)Met,Ser,Thr,(Stop)
B)Tyr,Ser,Cys,Thr
C)Ser,Tyr,Leu,Val
D)Met,Val,Asp,Met

Question 60

Mutations create new alleles that

A)are beneficial to the organism's fitness.
B)have no effect on the fitness of the organism.
C)decrease the fitness of the organism.
D)All answers are correct.
E)increase diversity at a genetic locus.

Question 61

Which of the following diseases is caused by something other than viruses?

A)the common cold and influenza
B)smallpox and mononucleosis
C)polio and rabies
D)AIDS and warts
E)diabetes

Question 62

The stage of viral replication in which the viral nucleic acid is released inside the cell is

A)penetration.
B)release.
C)attachment.
D)synthesis.
E)assembly.

Question 63

HIV is a

A)double-stranded DNA virus.
B)single-stranded RNA virus.
C)single-stranded DNA virus.
D)double-stranded RNA virus.
E)prion.

Question 64

Most antibiotics are not effective against viruses because they _____ and this does not affect the activity of viruses.

A)inhibit synthesis of cell walls
B)destroy DNA and RNA
C)inhibit all protein synthesis
D)target envelopes
E)inhibit reverse transcriptase

Question 65

The genetic information in viruses

A)is found in the nucleus of the virus.
B)is always DNA.
C)is either DNA or RNA.
D)is always RNA.
E)can be replicated outside of a cell.

Question 66

Viruses

A)consist of only a single cell.
B)are smaller than cells.
C)consist of multiple cells.
D)contain a nucleus.
E)contain ribosomes.

Question 67

A highly wound circle of RNA without a protein coat is a

A)virus.
B)virion.
C)viroid.
D)prion.
E)prophagE.

Question 68

If you were sorting labels for a diagram about viral replication,and if you found a part of the diagram saying that "the stage of viral replication in which viral components are put together to form new viruses," you would look for a label referring to

A)release.
B)assembly.
C)attachment.
D)penetration.
E)synthesis.

Question 69

The stage of viral replication in which the new viruses leave the host cell is

A)release.
B)attachment.
C)penetration.
D)synthesis.
E)assembly.

Question 70

The correct sequence of stages of viral replication is

A)attachment-synthesis-penetration-assembly-release
B)penetration-attachment-assembly-synthesis-release
C)penetration-attachment-synthesis-release-assembly
D)attachment-penetration-assembly-synthesis-release
E)attachment-penetration-synthesis-assembly-release

Question 71

HIV

A)is a retrovirus.
B)infects most mammals.
C)can be killed with antibiotics.
D)causes liver cancer.
E)can be transmitted through the skin.

Question 72

If genetic tests showed that a tomato plant had viral DNA integrated into its chromosomes without outward symptoms caused bthe virus,you could say that the tomato plant had

A)a rare form of viral infection.
B)a transgenic infection.
C)a lytic infection.
D)a systematic infection.
E)a lysogenic infection.

Question 73

A layer of membrane attached to a virus is called

A)an envelope.
B)a protein coat.
C)a chromosome.
D)a plasmiD.
E)a nucleus.

Question 74

If you were a vet examining a cat with an illness,and tests showed that a viral infection was causing the cat's cells to burst,you would say that the cat had

A)a rare form of viral infection.
B)a transgenic infection.
C)a lysogenic infection.
D)a lytic infection.
E)a systematic infection.

Question 75

An infectious protein is a

A)virus.
B)viroid.
C)prion.
D)virion.
E)prophagE.

Question 76

The enzyme that HIV uses to convert its RNA into DNA is

A)reverse transcriptase.
B)DNA polymerase.
C)RNA polymerase.
D)RNA integrase.
E)translasE.

Question 77

The stage of viral replication in which the virus binds to a cell surface receptor is

A)release.
B)penetration.
C)synthesis.
D)attachment.
E)assembly.

Question 78

One key reason why viruses are not considered living organisms is

A)viruses do not contain genetic information.
B)viruses do not reproduce on their own.
C)viruses are all smaller than the smallest known cells.
D)viruses do not contain a nucleus.
E)viruses can be frozen and still survivE.

Question 79

Our most potent weapon in the fight against viruses is

A)antibiotics.
B)sulfa drugs.
C)gene therapy.
D)surgery.
E)vaccinations.

Question 80

The stage of viral replication in which the host cell produces viral nucleic acids and proteins is

A)release.
B)attachment.
C)synthesis.
D)penetration.
E)assembly.