Deck 11: Gene Expression: From Transcription to Translation

Question 1

A "sense" RNA for a particular targeted protein is ___________.

A)an RNA having a sequence complementary to the mRNA of the targeted protein
B)the sequence of the mRNA that encoded the protein being targeted
C)a small RNA with a clover shape
D)an RNA always possessing catalytic activity
E)an RNA generally found in ribosomes that forges the peptide bond

Answer 1

B

Question 2

What did Archibald Garrod call diseases like alcaptonuria?

A)deadly diseases
B)inborn errors of transcription
C)homogentisms
D)errors
E)inborn errors of metabolism

Answer 2

E

Question 3

Once the F $\sigma$ factor leaves the core enzyme, what happens?

A)Transcription begins.
B)The core enzyme continues RNA elongation.
C)The core enzyme discontinues synthesis.
D)Transcription terminates.
E)The core enzyme backs up 25 nucleotides.

Answer 3

The core enzyme continues RNA elongation.

Question 4

What did Beadle and Tatum use to generate mutations in their experimental organism?

A)mustard gas
B)irradiation with ultraviolet light
C)fluorescent dyes
D)ethidium bromide
E)Coomassie blue

Question 5

An alcaptonuric lacks the enzyme that oxidizes which metabolite?

A)phenylalanine
B)tyrosine
C)homogentisic acid
D)asparagine
E)pantothenic acid

Question 6

Beadle and Tatum's research suggested that __________.

A)a gene carries the information to build lipids
B)a gene carries the information to build carbohydrates
C)a gene carries the information for the construction of a particular enzyme
D)a gene is made of RNA
E)a gene is made of DNA

Question 7

Sequences of DNA that are conserved and seen upstream of a transcription initiation site in roughly the same location from gene to gene in bacteria are called ________.

A)familiar sequences
B)conserved sequences
C)consensus sequences
D)avatars
E)consensons

Question 8

Who was the first to report that certain rare inherited diseases were caused by the absence of specific enzymes?

A)Charles Darwin
B)Archibald Garrod
C)George Beadle
D)Vernon Ingram
E)James Watson

Question 9

Once bound to the promoter, core RNA polymerase ________.

A)breaks the DNA chain in the start site region
B)melts the two DNA strands in the start site region
C)degrades the two DNA strands in the start site region
D)melts the two DNA strands in the termination site region

Question 10

What provides the energy that drives the polymerization of RNA from a DNA template?

A)nitrogenous base breakdown
B)deoxyribonucleoside triphosphate (dNTPs)bond breakage
C)ribonucleoside triphosphate (NTPs)bond breakage
D)ribose sugar hydrolysis
E)ribosome hydrolysis

Question 11

RNA polymerase is a processive enzyme which means that

A)it binds loosely to the DNA so it can slip off after each nucleotide.
B)it binds tightly to DNA so it only associates with one nucleotide.
C)it attaches to DNA for long stretches and moves from nucleotide to nucleotide.
D)it processes DNA templates into RNA or DNA.
E)it rapidly processes the entire DNA template at once.

Question 12

The site on DNA to which RNA polymerase binds before initiating transcription is called the ______.

A)terminator
B)operator
C)promoter
D)enhancer
E)silencer

Question 13

What was the new name of Beadle and Tatum's hypothesis after it was discovered that some enzymes were composed of more than one polypeptide chain?

A)the one gene-one enzyme hypothesis
B)the one gene-one polypeptide hypothesis
C)the one polypeptide-one enzyme hypothesis
D)the one polypeptide-one gene hypothesis
E)the one gene-two gene hypothesis

Question 14

The nucleotide at which transcription is initiated is called _____.

A)0
B)+1
C)-1
D)+2
E)-2

Question 15

Why has the one gene-one polypeptide hypothesis been modified in recent years?

A)It was found that RNA was the genetic material, not DNA.
B)Genes can be spliced differently to generate a variety of related polypeptides.
C)Enzymes sometimes consist of more than one polypeptide, each of which is coded for by its own gene.
D)Enzymes actually code for genes.
E)Polypeptides code for genes.

Question 16

Alcaptonuria is a genetic disease that is characterized by _________.

A)urine turning dark upon exposure to the air
B)mental retardation
C)paralysis
D)urine smelling and tasting like maple syrup
E)high fevers

Question 17

In what direction is an mRNA molecule synthesized?

A)3' to 5' direction
B)5' to 3' direction
C)N-terminal to C-terminal direction
D)C-terminal to N-terminal direction
E)N-terminal to 3' direction

Question 18

The enzyme that is responsible for the synthesis of RNA from a DNA template is called _______.

A)DNA-dependent DNA polymerase
B)DNA-dependent RNA polymerase
C)RNA-dependent RNA polymerase
D)RNA-dependent DNA polymerase
E)ribonuclease

Question 19

The reverse reaction of nucleic acid synthesis almost never happens. What prevents it?

A)The enzyme does not work in reverse.
B)Polynucleotides are too stable to depolymerize.
C)H bonds holding the strands together are too strong.
D)Nucleic acid synthesis is coupled to the highly exergonic pyrophosphate hydrolysis.
E)There is a large uptake of free energy.

Question 20

The _______ is located about 10 bases upstream from the initiation site. It has the consensus sequence ______ and is responsible for identifying the precise nucleotide at which ________ begins.

A)Pribnow box, TATAAT, transcription
B)Pribnow box, TTGACA, transcription
C)Pribnow box, TATAAT, translation
D)Portnoy box, TATAAT, transcription
E)Portnoy box, TATAAT, translation

Question 21

A cluster of genes coding for tRNAs is often referred to as ______.

A)tDNA
B)transferase
C)rDNA
D)t clusters
E)tDNase

Question 22

Modifications to the nucleotides of pre-rRNAs are made _________.

A)after translation
B)before transcription
C)after transcription
D)after mitosis
E)before mitosis

Question 23

What percentage of cellular RNA is rRNA?

A)less than 20%
B)more than 80%
C)50-60%
D)approximately 35%

Question 24

How would you describe the arrangement of the 5S rRNA genes?

A)tandem array with spacers
B)continuous genes
C)tandem array without spacers
D)4 introns between each protein
E)quartile array with duplex spacers

Question 25

The combination of DNA, RNA core enzyme and $\sigma$ factor is called _____.

A)an open complex
B)a transcription unit
C)a translation unit
D)a coding unit
E)a transcriptosome

Question 26

Where is the RNA polymerase II phosphorylated during its activation?

A)on the N-terminal end of the largest RNA polymerase II subunit
B)on the central 20 amino acids of the largest RNA polymerase II subunit
C)on the 3' end of the largest RNA polymerase II subunit
D)on the 5' end of the largest RNA polymerase II subunit
E)in the carboxyl-terminal domain (CTD)of the largest RNA polymerase II subunit

Question 27

What molecule is TFIIH known to phosphorylate?

A)a G protein
B)RNA polymerase II
C)peptidyltransferase
D)DNA helicase

Question 28

Which enzyme is responsible for synthesizing hnRNAs?

A)RNA polymerase I
B)RNA polymerase II
C)RNA polymerase III
D)reverse transcriptase
E)general transcription factors

Question 29

The chromosome regions containing most rDNA are gathered in __________.

A)terminators
B)nucleoli
C)nucleosomes
D)ribostores
E)telomeres

Question 30

What is the name of the RNA-degrading machine that consists of nearly a dozen different exonucleases and is thought to execute some of the enzymatic cleavages that occur during pre-rRNA processing?

A)endosome
B)exosome
C)nucleosome
D)heliosome
E)degradosome

Question 31

In mammalian cells employed in pulse-chase experiments, radiolabeled methyl groups appear first in which size RNA molecule that is a precursor to rRNA?

A)65S RNA
B)45S RNA
C)28S RNA
D)18S RNA
E)5.8S RNA

Question 32

Why are general transcription factors (GTFs)referred to as "general?"

A)The same transcription factors are required for the accurate initiation of transcription of a diverse array of genes in a wide variety of different organisms.
B)The same transcription factors are required for the accurate initiation of translation of a diverse array of genes in a wide variety of different organisms.
C)The same transcription factors are required for the accurate termination of transcription of a diverse array of genes in a wide variety of different organisms.
D)The same transcription factors are required for the accurate termination of translation of a diverse array of genes in a wide variety of different organisms.

Question 33

The promoter for tRNA genes (tDNA)is located ________.

A)at the 3' end of the gene
B)within the coding section of the gene
C)at the 5' end of the gene
D)far downstream of the gene
E)far upstream of the gene

Question 34

Most cellular RNA is in what form?

A)hnRNA
B)snoRNA
C)mRNA
D)rRNA
E)hmRNA

Question 35

Heterogeneous nuclear RNAs (hnRNAs)are _________.

A)tRNA precursors
B)mRNA precursors
C)rRNA precursors
D)snoRNA precursors
E)mature snRNAs

Question 36

You incubate eukaryotic cells for 30 minutes in [³H]uridine and then immediately kill the cells and extract the RNA. Where does the radiolabel appear after this experiment?

A)in larger molecular weight RNAs in the nucleus
B)in smaller molecular weight RNAs in the mitochondria
C)in smaller molecular weight RNAs in the cytoplasm
D)in larger molecular weight RNAs in the mitochondria
E)in moderately sized RNAs in the Golgi complex

Question 37

How would you describe the half-lives of rRNAs and tRNAs?

A)days or weeks long
B)minutes long
C)seconds long
D)hours long
E)years long

Question 38

RNA polymerase II promoters are located on the ________ side of each transcription unit.

A)3'
B)5'
C)N-terminal
D)C-terminal

Question 39

Pre-rRNAs have more ___________ than other RNA transcripts.

A)pseudouridine residues and thymidine residues
B)thymidine residues and methylated nucleotides
C)pseudouridine residues and methylated nucleotides
D)pseudouridines and pseudocytosines
E)methylated nucleotides and pseudocytosines

Question 40

A larger S value (Svedberg unit)for an RNA indicates that the RNA __________.

A)migrates more rapidly through a field of force during centrifugation
B)migrates less rapidly through a field of force during centrifugation
C)migrates more rapidly through a field of force during gel filtration
D)migrates more rapidly through a field of force during SDS polyacrylamide gel electrophoresis
E)migrates less rapidly through a field of force during SDS polyacrylamide gel electrophoresis

Question 41

Which strand of the double-stranded siRNA is cut in two and then dissociates from the pre-RISC?

A)the active strand
B)the passenger strand
C)the siRNA strand
D)the pedestrian strand
E)the silencer strand

Question 42

What appears to be the role of siRNA in destroying the target mRNA upon which it and its associated proteins act?

A)It cleaves the target mRNA.
B)It stabilizes the target mRNA.
C)It destabilizes the target mRNA's binding to its associated proteins.
D)It guides the RISC that cleaves the target mRNA to that target mRNA due to its complementarity to that molecule.
E)It activates the RISC complex ribonuclease.

Question 43

What is the presumed function of the siRNAs produced by mammalian oocytes?

A)They aid in fertilization.
B)They defend against the movement of transposable elements in the female germ cell line.
C)They defend against the movement of chromosomes in the female germ cell line.
D)They play a role in the regulation of meiosis.
E)They play a role in the regulation of oogenesis.

Question 44

Which of the phenomena below is responsible for the ability of one gene to code for more than one polypeptide?

A)transcription
B)alternative splicing
C)transposition
D)hybridization
E)exon shuffling

Question 45

The intermediate stage that the group II introns pass through while undergoing self-splicing is called the _____.

A)langolier
B)lanyard
C)lariat
D)lasso

Question 46

Which of the following binds to the TATA box?

A)CTD
B)tRNA
C)corticosteroid binding protein
D)TBP
E)PBT

Question 47

What is the name of the enzyme that cleaves dsRNA into the small, double-stranded fragments known as small-interfering RNAs (siRNAs)?

A)riboendonuclease
B)Dicer ribonuclease
C)deoxyribonuclease
D)RNA helicase
E)reverse transcriptase

Question 48

RNA interference can be used to __________ the production of a particular enzyme, allowing the effect of ___________ of the enzyme on the organism's _________ to be determined.

A)stop, deficiency, phenotype
B)enhance, deficiency, phenotype
C)stop, deficiency, genotype
D)enhance, overexpression, phenotype
E)stop, overexpression, genotype

Question 49

RNAi or dsRNA-mediated RNA interference is an example of a broader phenomenon that occurs widely in eukaryotes called __________.

A)RNA activation
B)RNA ascension
C)RNA silencing
D)RNA sussuration
E)RNA quieting

Question 50

A pri-miRNA is cleaved within the nucleus by an enzyme called _______ into a shorter, double-stranded, hairpin-shaped precursor called a ________.

A)Drosha, pre-miRNA
B)Drosha, pri-miRNA
C)Dicer, pre-miRNA
D)Dicer, pri-miRNA
E)Slicer, pre-miRNA

Question 51

The macromolecular complex that associates with each intron and splices it is called __________.

A)a splicer
B)an acrosome
C)a spliceosome
D)a splicing body
E)a splice engine

Question 52

Which of the following is NOT a normal property of eukaryotic mRNAs?

A)They contain a continuous nucleotide sequence encoding a specific polypeptide.
B)They are found in the cytoplasm and inside the Golgi complex.
C)They are attached to ribosomes when they are translated.
D)Most have a significant noncoding segment that does not direct assembly of amino acids.
E)They have special modifications at their 5' and 3' termini.

Question 53

How is the RISC directed to the target mRNA that it is destined to destroy?

A)The ribonuclease slicer directs the RISC to the cleavage site.
B)The single-stranded siRNA is complementary to the target mRNA and directs the RISC to it.
C)The passenger strand acts like a guide to direct the RISC to the target.
D)The siRNA is complementary to the slicer ribonuclease.
E)The siRNA is magnetically attracted to the target mRNA.

Question 54

Why does it make sense that cells would respond to the presence of dsRNAs with a mechanism such as RNAi?

A)dsRNAs are not produced by the cell's normal genetic activities.
B)dsRNAs are produced by the cell's normal genetic activities.
C)dsRNAs adversely affect mitochondria.
D)dsRNAs could cause degradation of nuclear DNA.
E)dsRNAs have a very abnormal interaction with proteins.

Question 55

Mammalian oocytes have recently been shown to produce siRNAs. What are they called?

A)exo-siRNAs
B)endo-siRNAs
C)endoRNAs
D)mamma-siRNAs
E)oo-siRNAs

Question 56

It is generally accepted that vertebrates do not utilize RNAi as a defense against viruses for what reason?

A)Vertebrates have no serious viral infections.
B)Vertebrate cell membranes resist viral attachment.
C)Vertebrate cell walls resist viral attachment.
D)Vertebrates rely instead on a well-developed immune system.

Question 57

The 3' end of most eukaryotic mRNAs contains a _________, while the 5' end has a _________.

A)poly(A)tail, methylated guanosine cap
B)poly(U)tail, methylated guanosine cap
C)methylated guanosine cap, poly(A)tail
D)poly(A)tail, sulfonated guanosine cap
E)methylated guanosine cap, poly(U)tail

Question 58

A small RNA encoded by the lin-4 gene was found in the nematode C. elegans. It was nearly complementary to segments in ________. These small RNAs were able to bind to the complementary mRNA, blocking its translation, which apparently triggers a transition to the next developmental stage.

A)the 3' untranslated region of specific mRNAs produced by the organism
B)the 5' untranslated region of specific mRNAs produced by the organism
C)the promoter of specific genes
D)the poly(A)tail of specific mRNAs
E)the 5'-methylguanosine cap of the mRNA

Question 59

Where is the pre-miRNA converted to miRNA by Dicer?

A)the nucleus
B)the cytoplasm
C)the mitochondria
D)the plasma membrane
E)the lysosome

Question 60

As life was first evolving, what molecule is thought to have performed double duty as the genetic material and catalyst of chemical reactions?

A)RNA
B)proteins
C)polypeptides
D)DNA
E)both proteins and polypeptides

Question 61

You discover alien life with a genetic system based on a DNA-like molecule, but it has 6 bases instead of 4 as happens on Earth. The proteins on the planet are built from combinations of 30 possible amino acids. What would be the minimum number of bases in each codon on this planet?

A)1
B)2
C)3
D)4
E)6

Question 62

What is the maximum number of tRNAs that a cell would be likely to have?

A)20
B)3
C)64
D)61
E)21

Question 63

Which molecule in plant cells has been linked with cell-to-cell movement of siRNA molecules?

A)Dicer DCL4
B)Drosha DCL6
C)Zucchini
D)RNA polymerase RDR8

Question 64

What is this difference between si/miRNAs and piRNAs?

A)piRNAs are longer than si/miRNAs.
B)The majority of mammalian piRNAs can be mapped to a small number of huge genomic loci, unlike si/mi RNAs.
C)The formation of piRNAs does not involve the formation of dsRNA precursors, unlike si/mi RNAs.
D)Formation of piRNAs does not involve cleavage by Dicer ribonuclease, but instead it depends on the endonuclease activity of the PIWI protein acting on a long, single stranded primary transcript.
E)All of these are correct.

Question 65

Which event is considered to be non-cell autonomous?

A)movement of mRNA between plant cells
B)movement of siRNAs between plant cells
C)compartmentalization of miRNAs in single plant cells
D)all are correct choices

Question 66

The CRISPR-cas9 system uses _______ as a template to locate and cleave specific___________ targets.

A)siRNA, DNA
B)siRNA, RNA
C)dsDNA, RNA
D)sgRNA, RNA
E)sgRNA, DNA

Question 67

What evidence shows that the genetic code is not overlapping?

A)Mutant proteins whose genes experience a change in only one nucleotide have a corresponding change in 3 consecutive amino acids.
B)Mutant proteins whose genes experience a change in only one nucleotide have a corresponding change in only 1 amino acid.
C)Mutant proteins are greatly increased in length relative to the nonmutated version.
D)Mutant proteins are greatly decreased in length relative to the nonmutated version.
E)Mutant proteins whose genes experience a change in only one nucleotide have a corresponding change in 6 consecutive amino acids.

Question 68

Which of the following is a correct statement about the CRISPR-cas9 system?

A)The CRISPR-cas9 system is only capable of DNA insertions.
B)The CRISPR-cas9 system was originally discovered in eukaryotes.
C)The CRISPR-cas9 system protects bacteria from viral infection
D)The CRISPR-cas9 system randomly cuts DNA at any sequence location

Question 69

A tRNA has an anticodon with the sequence 3'-UAC-5'. What would be the sequence of the complementary codon?

A)3'-UAC-5'
B)3'-AUG-5'
C)5'-AUG-3'
D)5'-AUC-3'
E)5'-ATG-3'

Question 70

The genetic code has 64 codons, while there are only 20 amino acids. Thus, some amino acids are coded for by more than one codon. As a result, the genetic code is said to be ________.

A)regenerate
B)degenerate
C)overlapping
D)nonoverlapping
E)nonspecific

Question 71

Where are the unusual bases of tRNAs predominantly concentrated?

A)in the stems
B)in the loops
C)at the 3' end
D)at the 5' end
E)in double-stranded regions

Question 72

Which enzyme, also responsible for siRNA formation, carves miRNAs from their double-stranded, fold-back RNA precursor (pre-miRNA)?

A)RNA polymerase
B)reverse transcriptase
C)Dicer ribonuclease
D)Drosha polymerase
E)Mincer ribonuclease

Question 73

Before the genetic code was actually known, Francis Crick predicted that it was degenerate. What piece of evidence led him to make this prediction?

A)All proteins looked the same.
B)All proteins were made of amino acids.
C)He noted that the base composition of the DNAs of various bacteria varied greatly while the amino acid composition of their proteins varied much less.
D)He noted that the base composition of the DNAs of various bacteria varied little while the amino acid composition of their proteins varied greatly overall.
E)The code was non-overlapping.

Question 74

The greatest similarities among codons that specify the same amino acid occur in the _________ of the triplet.

A)first two nucleotides
B)last two nucleotides
C)first and third nucleotides
D)third nucleotide
E)middle nucleotide

Question 75

How many codons code for an amino acid?

A)20
B)3
C)64
D)61
E)21

Question 76

With what protein does the double-stranded miRNA become associated? The RNA duplex then is disassembled and one of the single strands is incorporated into a RISC complex.

A)slicer
B)Mincer
C)an Argonaute protein
D)riscin
E)ribonuclease

Question 77

What does it mean to say the genetic code is universal?

A)The genetic code is the same everywhere in the Universe.
B)All of the organisms on Earth use the same genetic code with only minor variations.
C)The genetic code is found in all organisms but varies extensively.
D)The genetic code is minimal.
E)The genetic code is multiphasic.

Question 78

What is the supposed function of the loops in tRNAs?

A)They bind to amino acids.
B)They bind to other tRNAs.
C)They bind to mRNAs.
D)They serve as potential recognition sites for various proteins.
E)They increase the buoyant density of tRNAs.

Question 79

How do the unusual bases found in the loops in tRNA influence tRNA structure?

A)They disrupt H bond formation in the loop regions, causing the loops to form.
B)They bind to proteins that hold the loops open.
C)They disrupt hydrophobic interactions in the loop regions, causing the loops to form.
D)They prevent van der Waals interactions which prevent loop formation.
E)They disrupt H bond formation which causes complementary pairing in the stem regions.

Question 80

Another name for protein synthesis is _________.

A)transcription
B)transition
C)transubstantiation
D)translation
E)transition state