Deck 7: The Blueprint of Life, From DNA to Protein

Question 1

Which is true about prokaryotic (bacterial)RNA polymerase?

A)It is used during transcription.
B)It does not require a primer.
C)It has a detachable subunit,sigma factor,which recognizes the promoter.
D)It reads the template in the 3'-5' direction.
E)All of the choices are true.

Answer 1

All of the choices are true.

Question 2

DNA replication is

A)conservative.
B)interspersive.
C)semiconservative.
D)chain reference.

Answer 2

semiconservative.

Question 3

Which of the following is/are true of DNA replication?

A)It starts at the origin of replication.
B)Nucleotides are added to the 3' end.
C)It requires an RNA primer to get started.
D)It utilizes polymerases.
E)All of the choices are true.

Answer 3

All of the choices are true.

Question 4

The two strands of DNA are bonded to one another by

A)covalent bonds.
B)oxygen bonds.
C)hydrogen bonds.
D)carbon bonds.

Question 5

The specific sequence of nucleotides in the DNA to which the RNA polymerase binds is the

A)regulatory region.
B)promoter region.
C)sigma region.
D)core region.

Question 6

Which is true about DNA replication?

A)It is semiconservative.
B)It starts at an origin of replication.
C)It is bi-directional.
D)It requires RNA primers.
E)All of the choices are correct.

Question 7

The 3' end of DNA

A)refers to the end that has a hydroxyl group attached to the number 3 carbon of deoxyribose.
B)attaches to the 5' phosphate group of the incoming nucleotide.
C)always has thymine attached to it.
D)usually has guanine attached to it.
E)refers to the end that has a hydroxyl group attached to the number 3 carbon of deoxyribose AND attaches to the 5' phosphate group of the incoming nucleotide.

Question 8

Without changing the sequence or the orientation of the sequence(s),which is/are complementary to the sequence 5' AGGCUAAC 3'?

A)5' TCCGATTG 3'
B)3' TCCGATTC 5'
C)5' CTTAGCCT 3'
D)3' TAAGCTTA 5'
E)3' TCCGATTC 5' AND 5' CTTAGCCT 3'

Question 9

The lagging strand

A)is a type of RNA.
B)is found during RNA replication.
C)is necessary due to the properties of the enzymes and the antiparallel nature of DNA.
D)is always the bottom strand.

Question 10

GCCCAAAG is a molecule of

A)RNA.
B)DNA.
C)protein.
D)cannot tell as written.

Question 11

RNA is characterized by which one of the following features?

A)Deoxyribose
B)Thymine
C)Ribose
D)Double-stranded

Question 12

The term antiparallel

A)refers to the structure of single-stranded RNA.
B)is synonymous with semiconservative.
C)refers to the opposite orientation of the two strands in DNA.
D)refers to a type of prokaryotic replication.

Question 13

What structure is indicated by: 10A,15T,3G,7C?

A)Double-stranded RNA
B)Double-stranded DNA
C)Single-stranded RNA
D)Single-stranded DNA

Question 14

Which is not true of RNA?

A)It is usually single-stranded.
B)It functions in the cytoplasm.
C)It contains both uracil and thymine.
D)It contains ribose.

Question 15

The transcription terminator

A)results in a hairpin loop structure in RNA.
B)results in the polymerase falling off the DNA template.
C)stops DNA polymerase.
D)adds a terminator nucleotide to the RNA.
E)results in a hairpin loop structure in RNA AND results in the polymerase falling off the DNA template.

Question 16

Which pairing is incorrect?

A)A:T
B)G:C
C)A:U
D)A:G

Question 17

DNA is characterized by which of the following feature(s)?

A)Ribose
B)Single-stranded
C)Deoxyribose
D)Thymine
E)Deoxyribose AND thymine

Question 18

Which is true about the RNA transcript?

A)It is formed using the DNA minus strand as a template.
B)It has the same 5'-3' orientation as the DNA positive strand.
C)It is made in short fragments that are then stitched together.
D)The template starts at the promoter region.
E)It is formed using the DNA minus strand as a template,it has the same 5'-3' orientation as the DNA positive strand,AND the template starts at the promoter region.

Question 19

Which may be or is an RNA molecule?

A)AGCCTAC
B)GGGCCCA
C)GCCCUUA
D)AGCCTAC AND GGGCCCA
E)GGGCCCA AND GCCCUUA

Question 20

The phrase "one gene-one enzyme" is associated with the work of

A)Lederberg.
B)Watson and Crick.
C)Beadle and Tatum.
D)Mendel.

Question 21

The placement of the amino acid during translation is determined by the

A)DNase,which transcribes both molecules.
B)complementarity of the codon-anticodon.
C)sequence of nucleotides at the 5' end of the tRNA.
D)secondary structure of the newly forming protein.

Question 22

The genetic code has more than one codon for some amino acids.This is an example of

A)evolution.
B)stringency.
C)redundancy.
D)translation.

Question 23

What is the number of tRNA molecules that may be associated with translation?

A)16
B)20
C)64
D)Fewer than 64

Question 24

Bacteria use ______ attached TO the polymerase to direct RNA polymerase to promoters; eukaryotic cells use ______ that attach directly to the DNA first instead.

A)sigma factors; transcription factors
B)transcription factors; sigma factors
C)ribosomes; sigma factors
D)tRNA; rRNA

Question 25

The scientists responsible for the idea that RNA can act as a catalyst were

A)Watson and Crick.
B)Beadle and Tatum.
C)Altman and Cech.
D)Lederberg and Stanley.

Question 26

How many nucleotides are in a codon?

A)1
B)2
C)3
D)4
E)5

Question 27

A stop codon

A)codes for the stop amino acid s-methyl-methionine.
B)forms a hairpin loop forcing the ribosome to fall off.
C)codes for no amino acid.
D)enhances the binding of the e-polymerase.
E)codes for the stop amino acid s-methyl-methionine AND forms a hairpin loop forcing the ribosome to fall off.

Question 28

The ribosomes

A)move along the tRNA in a 3'-5' direction.
B)move along the mRNA in a 5'-3' direction.
C)move along the DNA in a 5'-3' direction.
D)provide a platform that brings the amino acids into a favorable position for joining.
E)move along the mRNA in a 5'-3' direction AND provide a platform that brings the amino acids into a favorable position for joining.

Question 29

Some segments of the precursor mRNA in eukaryotes are non-coding and are called

A)exons.
B)introns.
C)integrans.
D)uselessans.

Question 30

Signal transduction

A)is the relay of information about conditions outside a cell to inside the cell.
B)often relies on a two component system.
C)may involve phosphorylation of various molecules.
D)is used by certain pathogens to sense low magnesium conditions.
E)All of the choices are correct.

Question 31

Quorum sensing

A)is used by bacteria to sense the density of cells.
B)involves the production and monitoring of the amount of homoserine lactone present.
C)is used by bacteria to limit the density of bacteria.
D)is used by eukaryotes to sense the presence of bacteria.
E)is used by bacteria to sense the density of cells AND involves the production and monitoring of the amount of homoserine lactone present.

Question 32

Which molecule carries an anticodon?

A)DNA
B)mRNA
C)rRNA
D)tRNA

Question 33

There are _____ codons to code for the 20 possible amino acids.

A)20
B)30
C)64
D)61

Question 34

Post-translational modification may include

A)formation of exons and introns.
B)folding of the protein,often with the aid of chaperones.
C)removal of the signal sequence.
D)addition of glycine tags.
E)folding of the protein,often with the aid of chaperones,AND removal of the signal sequence.

Question 35

The E-site

A)is found on the RNA polymerase enzyme.
B)is responsible for the release of the tRNA.
C)is found on the 35S polysome.
D)is the aminoacyl site.
E)is responsible for the release of the tRNA AND is the aminoacyl site.

Question 36

Ribozymes

A)are complexes of ribosomes and RNA.
B)are self-catalytic RNA.
C)suggest that nucleic acids evolved before proteins.
D)are enzymes that degrade RNA and therefore have potential for clinical applications.
E)are self-catalytic RNA AND suggest that nucleic acids evolved before proteins.

Question 37

AUG

A)is only used as the start codon.
B)codes for methionine.
C)determines the reading frame.
D)is one of the stop codons.
E)codes for methionine AND determines the reading frame.

Question 38

In DNA sequence analysis

A)the + strand of DNA is used.
B)the start codon is ATG.
C)ORFs are searched for.
D)codon usage is a helpful indicator for protein coding areas.
E)All of the choices are correct.

Question 39

The P-site

A)is found on the polymerase enzyme.
B)is an allosteric site.
C)is a promoter site.
D)is the peptidyl site on the ribosome.
E)is an allosteric site AND is a promoter site.

Question 40

The amino acid that is placed first during translation in bacteria,mitochondria,and chloroplasts is

A)glycine.
B)methionine.
C)N-formyl-methionine.
D)serine.

Question 41

The molecules that bind to a repressor and cause it to no longer bind to the operator are called

A)activators.
B)repressors.
C)introns.
D)inducers.

Question 42

The set of genes in bacteria that are linked together and transcribed as a single unit is referred to as a(n)

A)operon.
B)regulon.
C)operator.
D)repressor.

Question 43

Antisense RNA is the complement of the plus strand and may be useful in inhibiting translation.

Question 44

DNA replication is usually unidirectional.

Question 45

CAP

A)is involved in positive control.
B)stands for cyclic amp protein.
C)works in conjunction with cAMP.
D)is involved in negative control.
E)is involved in positive control AND works in conjunction with cAMP.

Question 46

Adenine binds to thymine via three hydrogen bonds.

Question 47

The regulatory protein

A)binds to the promoter region of DNA.
B)may inhibit or enhance transcription.
C)may control translation of the operon.
D)affects the activity of the DNA polymerase.
E)binds to the promoter region of DNA AND affects the activity of the DNA polymerase.

Question 48

Activators

A)are involved in negative control.
B)are involved in positive control.
C)always bind to the promoter.
D)are allosteric proteins.
E)are involved in positive control AND are allosteric proteins.

Question 49

The genetic code is nearly universal.

Question 50

The DNA site to which the repressor protein binds is the

A)operon.
B)regulon.
C)operator.
D)repressor.

Question 51

Repressors

A)are involved in negative control.
B)are involved in positive control.
C)always bind to the promoter.
D)bind or do not bind to the operator depending on their shape (conformation).
E)are involved in negative control AND bind or do not bind to the operator depending on their shape (conformation).

Question 52

Negative control means a regulator molecule is

A)bound and transcription starts.
B)removed and transcription is inhibited.
C)bound and transcription is inhibited.
D)removed and transcription starts.
E)bound and transcription is inhibited AND removed and transcription starts.

Question 53

A codon consists of two nucleotides.

Question 54

One end of a strand of DNA is different from the other end.

Question 55

The anticodon determines which amino acid is linked to its tRNA.

Question 56

The minus strand of DNA serves as the template for RNA production.

Question 57

The lac operon

A)is an example of negative control.
B)is affected by catabolite repression.
C)produces lactose.
D)is an example of a regulon.
E)is an example of negative control AND is affected by catabolite repression.

Question 58

Gene regulation may entail

A)turning on genes only when needed.
B)turning off genes when not needed.
C)turning on or off entire groups of genes.
D)All of the choices are correct.

Question 59

RNAi

A)is the form of mRNA that initiates translation.
B)uses short pieces of single-stranded RNA to direct the degradation of specific RNA transcripts.
C)is a mechanism of genetic regulation found in eukaryotes.
D)is any chemical that inhibits transcription.
E)uses short pieces of single-stranded RNA to direct the degradation of specific RNA transcripts AND is a mechanism of genetic regulation found in eukaryotes.

Question 60

Operon(s)in bacteria

A)refers to a group of genes that are controlled in a coordinate fashion.
B)involve polycistronic mRNA.
C)involve monocistronic mRNA.
D)are also known as Wagnerons.
E)refers to a group of genes that are controlled in a coordinate fashion AND involve polycistronic mRNA.

Question 61

Why is it a good idea for a bacterial cell to be able to utilize glucose FIRST as an energy source (until it's used up),THEN switch to lactose?

A)Glucose is an easier compound to break down and obtain energy from than lactose.
B)Lactose cannot be used by bacterial cells as an energy source.
C)It's about conservation of energy-why expend the energy to make the extra enzymes for breaking down lactose when glucose is right there and doesn't need the extra enzymes for breakdown.
D)Glucose provides 10x as much energy when broken down as lactose.
E)Glucose is no easier compound to break down and obtain energy from than lactose AND It's about conservation of energy-why expend the energy to make the extra enzymes for breaking down lactose when glucose is right there and doesn't need the extra enzymes for breakdown.

Question 62

Cells are often ground up with abrasive to get to their internal enzymes/molecules,followed by removal of the abrasives.Here are three situations and three outcomes.What is the correct interpretation of the results? In situation #1,radioactive amino acids are added to cell material,and radioactive proteins are produced.In situation #2,radioactive amino acids,cell material,and the enzyme DNAse (degrades DNA)are added together.Radioactive proteins are still produced.In situation #3,the ground-up cell material is allowed to sit for 24 hours before radioactive amino acids and DNAse are added to it.No radioactive protein is produced.What is the most likely interpretation?

A)RNA polymerase has no activity after 24 hours,so no mRNA is transcribed and translated into radioactive proteinsin the last scenario.
B)The radioactivity in the amino acids is altering/degrading the tRNA molecules,leading to no protein production in the last scenario.
C)Natural RNAses present in the ground-up material will degrade any existing mRNAs in that 24-hour interval.Added DNAses breakdown DNA so that new RNAs are not synthesized.This will lead to a loss of capability to translate protein in the last scenario.
D)The results are not interpretable from the information given.

Question 63

A drug that inhibits the activity of bacterial DNA gyrase ______ be a good antibiotic because _______.

A)would; it would inhibit all DNA synthesis
B)would NOT; it would inhibit all DNA synthesis,even our own cell's DNA synthesis
C)would; it would selectively inhibit bacterial DNA synthesis due to differences between bacterial/human gyrase
D)would NOT; the DNA replication machinery could still function,even with impaired DNA gyrase enzyme

Question 64

Ribozymes are non-protein molecules with catalytic activity.

Question 65

Does the presence of introns/exons in eukaryotic cells provide more potential diversity in gene products (proteins)than is possible in prokaryotic cells?

A)It doesn't-this is a trick question.There's the same potential for gene products (proteins)in a bacterium with 1,000 genes as there is in a eukaryotic cell with 1,000 genes.
B)It does-each exon and each intron could be used individually and discretely to make agene product (protein).Since bacteria lack these,they will have less ability to create different proteins.
C)It does-exons/introns can be spliced together in different ways post-transcription to yield different mRNAs (and therefore,different proteins).Bacteria lack this system,so the gene you transcribe is translated into the only protein you'll end up getting.
D)It does-exons/introns can be spliced together in different ways at the DNA levelto eventually yield different mRNAs (and therefore,different proteins).Bacteria lack this system,so the gene you transcribe is translated into the only protein you'll end up getting.

Question 66

A graduate student is trying to isolate bacterial mRNA for an enzyme that will degrade trinitrotoluene (TNT).She's frustrated to find that the enzyme isn't produced when the bacterium in question is grown on nutrient agar.What might she do to solve the problem and obtain the mRNA?

A)Add nitrogen and toluene to the agar to drive up synthesis of TNT.
B)Add TNT to the agar-this will drive synthesis of the enzyme to degrade it,leading to production of the mRNA the student is looking for.
C)Remove glucose from the agar-this will cause the bacteria to shift to other compounds for their energy purposes.
D)Remove all sugars from the agar-this will cause the bacteria to shift to other compounds for their energy purposes.
E)Add TNT to the agar-this will drive synthesis of the enzyme to degrade it,leading to production of the mRNA the student is looking for AND remove all sugars from the agar-this will cause the bacteria to shift to other compounds for their energy purposes.

Question 67

Cells are often ground up with abrasive to get to their internal enzymes/molecules,followed by removal of the abrasives.Here are two situations and two outcomes.What is the correct interpretation of the results? In situation #1,radioactive amino acids are mixed with ground-up cell material.Radioactive proteins are produced.In situation #2,radioactive amino acids AND the enzyme RNAse (an enzyme that degrades RNA)are mixed with ground-up cell material.No radioactive proteins are produced.

A)The mRNA from the cell can be used to make proteins with the radioactive amino acids in the first situation.In the second situation,the mRNA is destroyed by the RNAse before it can be translated into protein containing the radioactive amino acids.
B)The DNA from the cell can be translated into protein using the radioactive amino acids in the first situation.The RNAse in the second situation degrades the ribosomal RNA (rRNA),preventing ribosomes from forming and making proteins with the radioactive amino acids.
C)The radioactivity in the amino acids corrupts the tRNA molecules,leading to no protein production in the second scenario.
D)The results cannot be interpreted-there isn't enough information given in the question.