Deck 7: DNA Structure and Gene Function

Question 1

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.

Answer 1

E
Explanation: Information flows from DNA to RNA to protein.

Question 2

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

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

Answer 2

B
Explanation: Together, transcription and translation take the information in a gene and convert it into a working protein.

Question 3

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.

Answer 3

D
Explanation: AT and GC base pairs are critical for the structure of DNA.

Question 4

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 5

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 6

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

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

Question 7

The double helix of DNA is composed of building blocks called

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

Question 8

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 9

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.

Question 10

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.

Question 11

Proteins that initiate transcription in eukaryotes by recognizing sequences within the promoter region of a gene and attracting RNA polymerase are called:

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

Question 12

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.

Question 13

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 14

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 15

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 16

RNA differs from DNA in many ways,including

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

Question 17

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 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

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 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

A change in a cell's DNA sequence is

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

Question 23

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 24

Changes in gene expression can be adaptive.

Question 25

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 26

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

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

Question 27

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 28

The length of a DNA sequence is ________ the mature mRNA transcribed from it because ________.

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

Question 29

Using the genetic code,how many amino acids are encoded by the following sequence from the start codon and up to the stop codon? AUGCUUGACUAAGUCCCC

A) 0
B) 1
C) 2
D) 3
E) 5
F) 6

Question 30

Mutations can be caused by errors in copying DNA.

Question 31

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 32

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

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

Question 33

"Mad cow disease" is caused by a viroid.

Question 34

In a "silent" mutation,the

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

Question 35

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

Question 36

Mutations can be caused by radiation.

Question 37

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

Question 38

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 39

Using the genetic code,what are the amino acids encoded by the sequence AUGUCAACGUGA?

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

Question 40

Mutations can be caused by chemicals.

Question 41

Mutations produce new alleles that may

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

Question 42

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

Question 43

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

Question 44

What did scientists discover was the primary cause for a genetically controlled language disorder in humans?

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 45

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

Question 46

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

Question 47

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 48

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

A) insertion
B) substitution
C) deletion
D) All answers are correct

Question 49

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

Question 50

If E.coli bacteria are grown in the absence of lactose

A) the repressor will not bind the operator, thus allowing transcription of the lac operon genes.
B) the repressor will bind the operator, thus allowing transcription of the lac operon genes.
C) the repressor will not bind the operator, thus preventing transcription of the lac operon genes.
D) the repressor will bind the operator, thus preventing transcription of the lac operon genes.
E) No answer is correct.

Question 51

In a DNA molecule,hydrogen bonds link the

A) complementary nitrogenous bases, thus keeping the two strands of DNA parallel to each other.
B) two strands of DNA end to end during transcription and translation.
C) two strands of DNA end to end during transcription only.
D) complementary deoxyribose sugars, thus maintaining a separation between the two DNA strands.

Question 52

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

Question 53

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 54

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 55

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

A) influenza
B) mononucleosis
C) polio
D) AIDS
E) diabetes

Question 56

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 57

If E.coli bacterium are grown in the presence of lactose

A) the repressor will bind the operator, thus allowing transcription of the lac operon genes.
B) the repressor will not bind the operator, thus preventing transcription of the lac operon genes.
C) the repressor will not bind the operator, thus allowing transcription of the lac operon genes.
D) the repressor will bind the operator, thus preventing transcription of the lac operon genes.
E) No answer is correct.

Question 58

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 59

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 60

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

Question 61

An infectious protein is a

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

Question 62

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 63

Viruses often spread from plant to plant by plant eating insects who physically injure the plant while eating the plant. What probably prevents viruses from easily entering plant cells?

A) the virus' cell walls
B) the plant's plasma membrane
C) the plant's cell wall
D) the virus' plasma membrane
E) the virus' protein coat

Question 64

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 65

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 66

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 67

You are sorting labels for a diagram about viral replication,and you find a part of the diagram that says: "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 68

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 69

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 70

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 71

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 72

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

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

Question 73

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 74

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.

Question 75

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 76

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 77

Our most potent weapon in the fight against viruses is

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

Question 78

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 79

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 80

If genetic tests showed that a tomato plant had viral DNA integrated into its chromosomes without outward symptoms caused by the 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.