Question 1

Organisms belonging to the archaea group possess a TATA-binding protein (TBP), but they are structurally very similar to members of the eubacteria (i.e., contain no nucleus, are single celled). What does this conundrum mean regarding the evolutionary relationships among the archaea, eubacteria, and eukaryotes?

Accepted Answer

The presence of a TATA-binding protein (...

Question 2

An in vitro transcription system that contains a bacterial gene initiates transcription from random points on the DNA. Which of the following proteins MOST likely is missing from the reaction?

Accepted Answer

A)   sigma factor
B)   rho factor
C)   RNA polymerase II
D)   TATA-binding protein (TBP) 
E)   TFIIDF) A) and B)
G) A) and C)

Question 3

Which of the following RNA molecules is required for the process of translation?

Accepted Answer

A)   crRNA
B)   tRNA
C)   snRNA
D)   snoRNA
E)   siRNAF) A) and D)
G) A) and C)

Question 4

_____ probably began the evolution of life on Earth.

Accepted Answer

A)   DNA
B)   RNA promoters
C)   DNA polymerases
D)   RNA polymerases
E)   RibozymesF) B) and C)
G) None of the above

Question 5

In eukaryotes, tRNAs are transcribed in:

Accepted Answer

A)   the nucleus and function in the nucleus
B)   the nucleus but function in the cytoplasm
C)   the cytoplasm and function in the cytoplasm
D)   both the nucleus and the cytoplasm and function in the cytoplasm
E)   the cytoplasm and function in the nucleusF) A) and E)
G) B) and D) B

Question 6

What is the function of eukaryotic RNA polymerase I?

Accepted Answer

A)   transcription of rRNA genes
B)   transcription of mRNA genes
C)   transcription of tRNA genes
D)   transcription of snRNAs
E)   initiation of transcription (but not elongation) F) C) and D)
G) B) and C)

Question 7

The DNA replication enzyme that most closely resembles RNA polymerase is:

Accepted Answer

A)   DNA polymerase I.
B)   DNA polymerase III.
C)   primase.
D)   telomerase.
E)   helicase.F) A) and B)
G) None of the above

Question 8

Which of the following features of the rho protein is primarily responsible for its ability to cause termination of transcription?

Accepted Answer

A)   recognizing unstructured RNA
B)   helicase activity
C)   migrating behind RNA polymerase
D)   RNA-binding activity
E)   polymerase activityF) C) and E)
G) C) and D)

Question 9

The polymerase that synthesizes which of the following molecules uses DNA as a template and synthesizes new strands from 5' to 3'?

Accepted Answer

A)   RNA only
B)   DNA only
C)   both RNA and DNA
D)   neither RNA nor DNAE) A) and C)
F) B) and C) C

Question 10

Over time, DNA replaced RNA as the primary carrier of genetic information, and the chemical stability of DNA is believed to be the key reason for this. Which attribute of DNA is the reason behind its chemical stability?

Accepted Answer

A)   DNA lacks a free hydroxyl group on the 2'-carbon atom of its sugar.
B)   Unlike RNA, DNA is usually double stranded.
C)   DNA does not usually form hairpin loops.
D)   One of the two pyrimidines found in DNA does not involve uracil.
E)   DNA contains thymines, which make it more chemically stable.F) D) and E)
G) B) and E)

Question 11

Explain why eukaryotic transcripts from the same RNA-polymerase-II-transcribed gene may vary in the sequences at the 3' end.

Accepted Answer

Eukaryotic transcripts from the same RNA...

Question 12

Prokaryotic promoters contain the sequence TATAAT at a position _____ from the transcription start.

Accepted Answer

A)   +1
B)   -1
C)   -10
D)   -25
E)   -35F) B) and E)
G) All of the above

Question 13

The discovery of ribozymes led to the theory that the evolution of life on Earth began with an "RNA world." Describe the chemical properties and functions of RNA that would allow it to be the basis of the first self-replicating systems.

Accepted Answer

RNA, or ribonucleic acid, has several ch...

Question 14

Mutations occurred in one of the inverted repeat sequences within the rho-independent terminator sequence of a bacterium. What would likely be the consequence of this mutation? (Select all that apply.)

Accepted Answer

A)   The transcription may end prematurely.
B)   The transcription may not be initiated at all.
C)   The transcription may be delayed.
D)   The RNA transcript may not be able to dissociate from the DNA template.
E)   The transcription may not terminate and result in much longer RNA.F) All of the above
G) A) and B)

Question 15

How are enhancers different from promoters?

Accepted Answer

Enhancers and promoters are both essenti...

Question 16

Transcription of a gene using what is normally the nontemplate strand can be accomplished using standard genetic engineering techniques to move the promoter. The resulting RNA is called "antisense RNA." Antisense RNA is often used to prevent production of a protein. Explain how antisense RNA would interact with RNA normally made by the gene and how this would interfere with protein production.

Accepted Answer

Antisense RNA is a single-stranded RNA m...

Question 17

The following diagram represents a transcription unit.  Which region(s) , A, B, and/or C, would be transcribed into an RNA transcript? (Select all that apply.)

Accepted Answer

A)   A
B)   B
C)   CD) B) and C)
E) A) and C)

Question 18

A new mutation in Saccharomyces cerevisiae, a eukaryotic yeast, causes the cells to be unable to produce the amino acid histidine. Specifically, they cannot catalyze the first reaction in the histidine biosynthesis pathway. When examined closely, they are producing a completely wild-type enzyme for this reaction but at greatly reduced levels. Explain the mutation.

Accepted Answer

The scenario described suggests that the...

Question 19

In prokaryotic RNA polymerases, the holoenzyme consists of the core enzyme and the:

Accepted Answer

A)   rho factor.
B)   TFIID.
C)   TBP.
D)   omega subunit.
E)   sigma factor.F) A) and D)
G) A) and C)

Question 20

Describe how the activities and requirements of prokaryotic RNA polymerase and eukaryotic RNA polymerase II are both similar and different.

Accepted Answer

The activities and requirements of prokaryotic RNA polymerase and eukaryotic RNA polymerase II are both similar and different in several ways.

Similarities:
1. Both prokaryotic RNA polymerase and eukaryotic RNA polymerase II are responsible for transcribing DNA into RNA.
2. They both require a DNA template and ribonucleoside triphosphates (NTPs) as substrates for RNA synthesis.
3. Both enzymes require divalent metal ions, such as Mg2+, for catalysis of the RNA synthesis reaction.
4. They both require specific promoter sequences on the DNA to initiate transcription.

Differences:
1. Prokaryotic RNA polymerase is a single enzyme complex, while eukaryotic RNA polymerase II is a multi-subunit complex.
2. Eukaryotic RNA polymerase II requires additional transcription factors, such as TFIIB, TFIID, and TFIIH, for transcription initiation, which are not required by prokaryotic RNA polymerase.
3. Eukaryotic RNA polymerase II undergoes extensive post-translational modifications, such as phosphorylation, to regulate its activity, while prokaryotic RNA polymerase does not undergo similar modifications.
4. Eukaryotic RNA polymerase II transcribes mRNA, while prokaryotic RNA polymerase transcribes both mRNA and non-coding RNAs, such as tRNAs and rRNAs.

In summary, while both prokaryotic RNA polymerase and eukaryotic RNA polymerase II share some common activities and requirements for transcription, they also have distinct differences in their structure, regulation, and specific functions.

Exam 13: Transcription

Correct Answer
Answered by ExamLex AI
The presence of a TATA-binding protein (...
View Answer

An in vitro transcription system that contains a bacterial gene initiates transcription from random points on the DNA. Which of the following proteins MOST likely is missing from the reaction?

Correct Answer
verified

Which of the following RNA molecules is required for the process of translation?

Correct Answer
verified

_____ probably began the evolution of life on Earth.

Correct Answer
verified

In eukaryotes, tRNAs are transcribed in:

Correct Answer
verified
B

What is the function of eukaryotic RNA polymerase I?

Correct Answer
verified

The DNA replication enzyme that most closely resembles RNA polymerase is:

Correct Answer
verified

Which of the following features of the rho protein is primarily responsible for its ability to cause termination of transcription?

Correct Answer
verified

The polymerase that synthesizes which of the following molecules uses DNA as a template and synthesizes new strands from 5' to 3'?

Correct Answer
verified
C

Over time, DNA replaced RNA as the primary carrier of genetic information, and the chemical stability of DNA is believed to be the key reason for this. Which attribute of DNA is the reason behind its chemical stability?

Correct Answer
verified

Explain why eukaryotic transcripts from the same RNA-polymerase-II-transcribed gene may vary in the sequences at the 3' end.

Correct Answer
Answered by ExamLex AI
Eukaryotic transcripts from the same RNA...
View Answer

Prokaryotic promoters contain the sequence TATAAT at a position _____ from the transcription start.

Correct Answer
verified

The discovery of ribozymes led to the theory that the evolution of life on Earth began with an "RNA world." Describe the chemical properties and functions of RNA that would allow it to be the basis of the first self-replicating systems.

Correct Answer
Answered by ExamLex AI
RNA, or ribonucleic acid, has several ch...
View Answer

Mutations occurred in one of the inverted repeat sequences within the rho-independent terminator sequence of a bacterium. What would likely be the consequence of this mutation? (Select all that apply.)

Correct Answer
verified

How are enhancers different from promoters?

Correct Answer
Answered by ExamLex AI
Enhancers and promoters are both essenti...
View Answer

Correct Answer
Answered by ExamLex AI
Antisense RNA is a single-stranded RNA m...
View Answer

The following diagram represents a transcription unit. Which region(s) , A, B, and/or C, would be transcribed into an RNA transcript? (Select all that apply.)

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The scenario described suggests that the...
View Answer

In prokaryotic RNA polymerases, the holoenzyme consists of the core enzyme and the:

Correct Answer
verified

Describe how the activities and requirements of prokaryotic RNA polymerase and eukaryotic RNA polymerase II are both similar and different.

Exam 13: Transcription

Correct AnswerAnswered by ExamLex AIThe presence of a TATA-binding protein (...View AnswerShow Answer

An in vitro transcription system that contains a bacterial gene initiates transcription from random points on the DNA. Which of the following proteins MOST likely is missing from the reaction?

Correct AnswerverifiedShow Answer

Which of the following RNA molecules is required for the process of translation?

Correct AnswerverifiedShow Answer

_____ probably began the evolution of life on Earth.

Correct AnswerverifiedShow Answer

In eukaryotes, tRNAs are transcribed in:

Correct AnswerverifiedB

What is the function of eukaryotic RNA polymerase I?

Correct AnswerverifiedShow Answer

The DNA replication enzyme that most closely resembles RNA polymerase is:

Correct AnswerverifiedShow Answer

Which of the following features of the rho protein is primarily responsible for its ability to cause termination of transcription?

Correct AnswerverifiedShow Answer

The polymerase that synthesizes which of the following molecules uses DNA as a template and synthesizes new strands from 5' to 3'?

Correct AnswerverifiedC

Over time, DNA replaced RNA as the primary carrier of genetic information, and the chemical stability of DNA is believed to be the key reason for this. Which attribute of DNA is the reason behind its chemical stability?

Correct AnswerverifiedShow Answer

Explain why eukaryotic transcripts from the same RNA-polymerase-II-transcribed gene may vary in the sequences at the 3' end.

Correct AnswerAnswered by ExamLex AIEukaryotic transcripts from the same RNA...View AnswerShow Answer

Prokaryotic promoters contain the sequence TATAAT at a position _____ from the transcription start.

Correct AnswerverifiedShow Answer

The discovery of ribozymes led to the theory that the evolution of life on Earth began with an "RNA world." Describe the chemical properties and functions of RNA that would allow it to be the basis of the first self-replicating systems.

Correct AnswerAnswered by ExamLex AIRNA, or ribonucleic acid, has several ch...View AnswerShow Answer

Mutations occurred in one of the inverted repeat sequences within the rho-independent terminator sequence of a bacterium. What would likely be the consequence of this mutation? (Select all that apply.)

Correct AnswerverifiedShow Answer

How are enhancers different from promoters?

Correct AnswerAnswered by ExamLex AIEnhancers and promoters are both essenti...View AnswerShow Answer

Correct AnswerAnswered by ExamLex AIAntisense RNA is a single-stranded RNA m...View AnswerShow Answer

The following diagram represents a transcription unit. Which region(s) , A, B, and/or C, would be transcribed into an RNA transcript? (Select all that apply.)

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AIThe scenario described suggests that the...View AnswerShow Answer

In prokaryotic RNA polymerases, the holoenzyme consists of the core enzyme and the:

Correct AnswerverifiedShow Answer

Describe how the activities and requirements of prokaryotic RNA polymerase and eukaryotic RNA polymerase II are both similar and different.

Correct Answer
Answered by ExamLex AI
The presence of a TATA-binding protein (...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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B

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C

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Correct Answer
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Eukaryotic transcripts from the same RNA...
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Correct Answer
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Correct Answer
Answered by ExamLex AI
RNA, or ribonucleic acid, has several ch...
View Answer

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
Enhancers and promoters are both essenti...
View Answer

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Antisense RNA is a single-stranded RNA m...
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Correct Answer
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The scenario described suggests that the...
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