Question 1

What is the utility of the SELEX protocol and how does it work?

Accepted Answer

The SELEX (Systematic Evolution of Ligan...

Question 2

Which statement about the reverse transcriptases of retroviruses and the RNA replicases of other single-stranded RNA viruses, such as R17 and influenza virus, is CORRECT?

Accepted Answer

A)   Both enzymes can synthesize either RNA or DNA from an RNA template strand.
B)   Both enzymes can utilize DNA in addition to RNA as a template strand.
C)   Both enzymes carry the specificity for the RNA of their own virus.
D)   Both enzymes have error rates similar to those of cellular RNA polymerases.
E)   Both enzymes require host-encoded subunits for their replication function.

Question 3

Which statement about E. coli RNA polymerase (core enzyme)  is FALSE?

Accepted Answer

A)   In the absence of the  σ\sigmaσ  subunit, core polymerase has little specificity for where initiation begins.
B)   The core enzyme contains several different subunits.
C)   The core enzyme has no polymerizing activity until the  σ\sigmaσ  subunit is bound.
D)   The RNA chain grows in a 5'  →\rightarrow→   3' direction.
E)   The RNA product is complementary to the DNA template.

Question 4

The excision (splicing)  of many group I introns requires, in addition to the primary transcript RNA:

Accepted Answer

A)   a cytosine nucleoside or nucleotide and a protein enzyme.
B)   a guanine nucleoside or nucleotide (only) .
C)   a protein enzyme only.
D)   a small nuclear RNA and a protein enzyme.
E)   ATP, NAD, and a protein enzyme.

Question 5

Which property does NOT apply to RNA polymerase from E. coli (core enzyme alone) ?

Accepted Answer

A)   It can extend an RNA chain and initiate a new chain.
B)   It is required for the synthesis of mRNA, rRNA, and tRNA in E. coli.
C)   It produces an RNA polymer that begins with a 5'-triphosphate.
D)   It recognizes specific start signals in DNA.
E)   It requires all four ribonucleoside triphosphates and a DNA template.

Question 6

Which statement is FALSE regarding telomerase?

Accepted Answer

A)   This enzyme requires a DNA component as a cofactor.
B)   This enzyme is a DNA polymerase.
C)   This enzyme extends the 3' end of a linear nucleic acid structure.
D)   This enzyme uses dGTP and dTTP as substrates.
E)   This enzyme synthesizes nucleic acids in a 5'to 3'direction.

Question 7

Which statement about the synthesis of rRNA and tRNA in E. coli is TRUE?

Accepted Answer

A)   Both rRNA and some tRNAs are part of the same primary transcript.
B)   Each rRNA sequence (16S, 23S, 5S)  is transcribed as a separate primary transcript.
C)   Primary tRNA transcripts undergo methylation, but rRNA sequences are not methylated.
D)   The tRNA sequences all lie at the 3'end of the rRNA transcripts.
E)   There is a single copy of the rRNA genes.

Question 8

Which item(s)  can be described as a ribozyme(s) ?

Accepted Answer

A)   group I introns
B)   RNase P
C)   group II introns
D)   both group I and group II introns but not RNase P
E)   Group I introns, group II introns, and RNase P can all be described as ribozymes.

Question 9

Which process is associated with the carboxy-terminal domain (CTD)  of RNA polymerase II in eukaryotes?

Accepted Answer

A)   formation of spliceosomes
B)   attachment of the 5' cap to mRNA
C)   polyadenylation of the 3' end of mRNA
D)   phosphorylation and dephosphorylation
E)   All of the answers are correct.

Question 10

Which statement does NOT indicate how retrotransposons and retroviruses are similar to each other?

Accepted Answer

A)   Both contain long terminal repeated sequences.
B)   Both are able to produce RNA products from their DNA.
C)   Both contain reverse transcriptase coding regions.
D)   Both contain envelope protein coding sequences.
E)   Both integrate into a host genome.

Question 11

The reverse transcriptase of an animal RNA virus catalyzes:

Accepted Answer

A)   degradation of the RNA strand in a DNA-RNA hybrid.
B)   insertion of the viral genome into a chromosome of the host (animal)  cell.
C)   RNA formation in the 3'  →\rightarrow→  5' direction.
D)   RNA synthesis, but not DNA synthesis.
E)   synthesis of an antisense RNA transcript.

Question 12

In order for RNA polymerase II to create a transcript, what is NOT necessary?

Accepted Answer

A)   magnesium
B)   dNTPs
C)   topoisomerases
D)   zinc
E)   All of these are necessary.

Question 13

List two main functions of the 5' cap structure.
99.4 distinct complexes bind to the carboxyl-terminal domain (CTD) of RNA polymerase II. List these complexes and state the consequences of the interaction with CTD.

Accepted Answer

The 5'cap structure has two main functio...

Question 14

Transfer RNAs have several bases in addition to the normal four found in RNA. How are these rare bases incorporated into the tRNA molecule?

Accepted Answer

Transfer RNAs (tRNAs) are crucial molecu...

Question 15

Which statement is NOT true about telomerase?

Accepted Answer

A)   Telomerase is a reverse transcriptase.
B)   Telomerase utilizes a tRNA template.
C)   The primer for telomerase is the 3'-end of the DNA chromosomes.
D)   Telomerase synthesizes DNA in the 5'  →\rightarrow→   3' direction.
E)   Telomerase consists of both RNA and protein.

Question 16

The 5'-terminal cap structure of eukaryotic mRNAs is a(n) :

Accepted Answer

A)   7-methylcytosine joined to the mRNA via a 2',3'-cyclic linkage.
B)   7-methylguanosine joined to the mRNA via a 5'  →\rightarrow→   3' diphosphate linkage.
C)   7-methylguanosine joined to the mRNA via a 5'  →\rightarrow→  5' triphosphate linkage.
D)   N6-methyladenosine joined to the mRNA via a 5'  →\rightarrow→   5' phosphodiester bond.
E)   O6-methylguanosine joined to the mRNA via a 5'  →\rightarrow→   5' triphosphate linkage.

Question 17

Which statement does NOT accurately describe a difference between RNA synthesis by polynucleotide phosphorylase and RNAP?

Accepted Answer

A)   RNAP is a bacterial enzyme, while polynucleotide phosphorylase is not.
B)   RNAP requires a template, while polynucleotide phosphorylase does not.
C)   RNAP produces a specific product, while polynucleotide phosphorylase does not.
D)   RNAP uses nucleotide triphosphates as substrates, while polynucleotide phosphorylase uses nucleotide diphosphates.
E)   RNAP synthesizes RNA, while polynucleotide phosphorylase can synthesize or degrade RNA.

Question 18

Name four general types of posttranscriptional processing reactions that are observed in RNA. Briefly (one sentence or less) point out an example of each type. In your example, identify the type of RNA molecule involved (tRNA, mRNA, rRNA, etc.), the type of "processing" involved, and whether the example is characteristic of eukaryotes or prokaryotes, or both. Do not describe specific genes, sequences, complicated structures, or enzymes.

Accepted Answer

1. Splicing: Removal of introns from pre...

Question 19

Which factor is NOT involved in mRNA processing in vertebrates?

Accepted Answer

A)   30S pre-rRNA
B)   the nucleoleus
C)   ribonucleases
D)   snoRNAs
E)   snoRNPs

Question 20

What statement is TRUE regarding synthesis of nucleic acids by E. coli RNA polymerase?

Accepted Answer

A)   The RNA/DNA hybrid assumes a B-form DNA conformation.
B)   The RNA/DNA hybrid is antiparallel.
C)   The RNA/DNA hybrid is between 10 and 20 base pairs long.
D)   Unwinding the DNA duplex creates negative supercoils in the template DNA.
E)   None of the statements is true.

Exam 26: RNA Metabolism

Which statement about the reverse transcriptases of retroviruses and the RNA replicases of other single-stranded RNA viruses, such as R17 and influenza virus, is CORRECT?

Correct Answer
verified

Which statement about the synthesis of rRNA and tRNA in E. coli is TRUE?

Correct Answer
verified

The excision (splicing) of many group I introns requires, in addition to the primary transcript RNA:

Correct Answer
verified

In order for RNA polymerase II to create a transcript, what is NOT necessary?

Correct Answer
verified

What is the utility of the SELEX protocol and how does it work?

Correct Answer
Answered by ExamLex AI
The SELEX (Systematic Evolution of Ligan...
View Answer

Which process is associated with the carboxy-terminal domain (CTD) of RNA polymerase II in eukaryotes?

Correct Answer
verified

List two main functions of the 5' cap structure. 99.4 distinct complexes bind to the carboxyl-terminal domain (CTD) of RNA polymerase II. List these complexes and state the consequences of the interaction with CTD.

Correct Answer
Answered by ExamLex AI
The 5'cap structure has two main functio...
View Answer

Transfer RNAs have several bases in addition to the normal four found in RNA. How are these rare bases incorporated into the tRNA molecule?

Correct Answer
Answered by ExamLex AI
Transfer RNAs (tRNAs) are crucial molecu...
View Answer

Which statement about E. coli RNA polymerase (core enzyme) is FALSE?

Correct Answer
verified

Which statement is NOT true about telomerase?

Correct Answer
verified

Which statement does NOT indicate how retrotransposons and retroviruses are similar to each other?

Correct Answer
verified

The reverse transcriptase of an animal RNA virus catalyzes:

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
1. Splicing: Removal of introns from pre...
View Answer

Which property does NOT apply to RNA polymerase from E. coli (core enzyme alone) ?

Correct Answer
verified

The 5'-terminal cap structure of eukaryotic mRNAs is a(n) :

Correct Answer
verified

What statement is TRUE regarding synthesis of nucleic acids by E. coli RNA polymerase?

Correct Answer
verified

Which factor is NOT involved in mRNA processing in vertebrates?

Correct Answer
verified

Which statement does NOT accurately describe a difference between RNA synthesis by polynucleotide phosphorylase and RNAP?

Correct Answer
verified

Which item(s) can be described as a ribozyme(s) ?

Correct Answer
verified

Which statement is FALSE regarding telomerase?

Correct Answer
verified

Exam 26: RNA Metabolism

Which statement about the reverse transcriptases of retroviruses and the RNA replicases of other single-stranded RNA viruses, such as R17 and influenza virus, is CORRECT?

Correct AnswerverifiedShow Answer

Which statement about the synthesis of rRNA and tRNA in E. coli is TRUE?

Correct AnswerverifiedShow Answer

The excision (splicing) of many group I introns requires, in addition to the primary transcript RNA:

Correct AnswerverifiedShow Answer

In order for RNA polymerase II to create a transcript, what is NOT necessary?

Correct AnswerverifiedShow Answer

What is the utility of the SELEX protocol and how does it work?

Correct AnswerAnswered by ExamLex AIThe SELEX (Systematic Evolution of Ligan...View AnswerShow Answer

Which process is associated with the carboxy-terminal domain (CTD) of RNA polymerase II in eukaryotes?

Correct AnswerverifiedShow Answer

List two main functions of the 5' cap structure. 99.4 distinct complexes bind to the carboxyl-terminal domain (CTD) of RNA polymerase II. List these complexes and state the consequences of the interaction with CTD.

Correct AnswerAnswered by ExamLex AIThe 5'cap structure has two main functio...View AnswerShow Answer

Transfer RNAs have several bases in addition to the normal four found in RNA. How are these rare bases incorporated into the tRNA molecule?

Correct AnswerAnswered by ExamLex AITransfer RNAs (tRNAs) are crucial molecu...View AnswerShow Answer

Which statement about E. coli RNA polymerase (core enzyme) is FALSE?

Correct AnswerverifiedShow Answer

Which statement is NOT true about telomerase?

Correct AnswerverifiedShow Answer

Which statement does NOT indicate how retrotransposons and retroviruses are similar to each other?

Correct AnswerverifiedShow Answer

The reverse transcriptase of an animal RNA virus catalyzes:

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AI1. Splicing: Removal of introns from pre...View AnswerShow Answer

Which property does NOT apply to RNA polymerase from E. coli (core enzyme alone) ?

Correct AnswerverifiedShow Answer

The 5'-terminal cap structure of eukaryotic mRNAs is a(n) :

Correct AnswerverifiedShow Answer

What statement is TRUE regarding synthesis of nucleic acids by E. coli RNA polymerase?

Correct AnswerverifiedShow Answer

Which factor is NOT involved in mRNA processing in vertebrates?

Correct AnswerverifiedShow Answer

Which statement does NOT accurately describe a difference between RNA synthesis by polynucleotide phosphorylase and RNAP?

Correct AnswerverifiedShow Answer

Which item(s) can be described as a ribozyme(s) ?

Correct AnswerverifiedShow Answer

Which statement is FALSE regarding telomerase?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The SELEX (Systematic Evolution of Ligan...
View Answer

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The 5'cap structure has two main functio...
View Answer

Correct Answer
Answered by ExamLex AI
Transfer RNAs (tRNAs) are crucial molecu...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
1. Splicing: Removal of introns from pre...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified