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Which of the following molecules is made of nucleotides joined by phosphodiester bonds that connect the 2' OH to the 5' phosphate?


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

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If you were asked to isolate total RNA from two unknown samples and then were required to identify if the RNA was from prokaryotes or eukaryotes, what aspects regarding the classes of RNA present would help you distinguish one from the other?

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To distinguish whether the RNA is from p...

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Which one of the following statements regarding eukaryotic transcription is NOT true?


A) Eukaryotic transcription involves a core promoter and a regulatory promoter.
B) There is no one generic promoter.
C) A group of genes is transcribed into a polycistronic RNA.
D) Chromatin remodeling is necessary before certain genes are transcribed.
E) There are several different types of RNA polymerase.

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What would be the consequence of a mutation in the gene that encodes sigma factor for bacterial transcription?


A) The initiation of transcription may begin at random points of the DNA template.
B) The RNA polymerase may not be released from the DNA template.
C) Transcription may be delayed indefinitely, which may kill the cell.
D) The RNA transcript may not be able to dissociate from the DNA template.
E) The transcription may end prematurely, resulting in shorter mRNA transcript.

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The discovery of ribozymes led to the theory that the evolution of life on Earth began with an "RNA world." Describe how the current cellular roles of RNA support this theory.

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The discovery of ribozymes, which are RN...

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Two sequences of a prokaryotic promoter are shown below. Sequence 1 is the wild-type sequence, and sequence 2 is a mutant sequence (mutation shown in bold) that results in increased transcription of the gene. Explain why sequence 2 shows this phenotype. Sequence 1 \quad\quad\quad\quad\quad\quad\quad Sequence 2 10- 10\quad\quad\quad\quad\quad\quad\quad\quad\quad10- 10 ...CGAATAATGAA... \quad\quad ...CGTATAATGAA...

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The mutation in sequence 2 changes the n...

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Which of the following statements is TRUE regarding the termination of transcription?


A) In some organisms, transcription terminates thousands of nucleotides past the coding sequence.
B) Transcription typically terminates precisely at the hairpin loop terminator sequence.
C) In prokaryotes, transcription terminates as soon as rho has bound to the RNA.
D) In yeast, transcription terminates as soon as Rat1 has bound to the RNA.

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The following diagram represents the transcription unit and corresponding RNA transcripts as "Christmas-tree-like" structures captured in the electron micrograph. The following diagram represents the transcription unit and corresponding RNA transcripts as  Christmas-tree-like  structures captured in the electron micrograph.   - Which of the following statements CORRECTLY describes the reason as to why the transcription unit looks like a  Christmas tree  with different length of tree branches along the DNA  tree trunk ? A)  Depending on where the transcription begins on the DNA template, different lengths of transcripts get generated. B)  Each position on the DNA dictates the specific length of the RNA transcript generated from that particular position. C)  The transcript randomly grows from the DNA without any particular reason. D)  A single DNA can be transcribed many times continuously, and the RNA transcript gets longer as the transcription apparatus moves down the DNA. E)  There is no known reason for the transcription unit to assume the  Christmas-tree-like  shape. - Which of the following statements CORRECTLY describes the reason as to why the transcription unit looks like a "Christmas tree" with different length of tree branches along the DNA "tree trunk"?


A) Depending on where the transcription begins on the DNA template, different lengths of transcripts get generated.
B) Each position on the DNA dictates the specific length of the RNA transcript generated from that particular position.
C) The transcript randomly grows from the DNA without any particular reason.
D) A single DNA can be transcribed many times continuously, and the RNA transcript gets longer as the transcription apparatus moves down the DNA.
E) There is no known reason for the transcription unit to assume the "Christmas-tree-like" shape.

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The TATA-binding protein (TBP) binds to the TATA box sequence in eukaryotic promoters. What is its function in transcriptional initiation?


A) It blocks access of RNA polymerase to the promoter until removed by general transcription factors.
B) It is the subunit of prokaryotic RNA polymerase that is required to recognize promoters.
C) It modifies histones so that nucleosomes can be removed from DNA for transcription.
D) It bends and partly unwinds DNA at a promoter.
E) It creates a phosphodiester bond between the nucleotides.

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When does sigma factor normally dissociate from RNA polymerase?


A) after transcription has terminated
B) after the process of initiation
C) after the addition of nucleosomes
D) after the binding of rho
E) following the addition of nucleosomes

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What are the three different RNA polymerases found in all eukaryotes and what types of genes do they transcribe?

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In eukaryotic cells, there are three dif...

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Which of the following molecules is synthesized using triphosphate nucleotides as a substrate for a polymerase enzyme that forms phosphodiester bonds?


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

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Which of the following is a sequence of DNA where transcription is initiated?


A) hairpin loop
B) TBP
C) initiator
D) sigma factor
E) promoter

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In prokaryotes, rho-independent transcription termination depends on a secondary structure formed in:


A) the RNA polymerase that is transcribing the gene.
B) the DNA template.
C) the RNA that is being transcribed.
D) a protein factor that binds to RNA polymerase.
E) a protein factor that binds to the RNA that is being transcribed.

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In a transcription reaction, two phosphate groups are cleaved from the incoming:


A) deoxyribonucleoside diphosphate.
B) deoxyribonucleoside triphosphate.
C) ribonucleoside diphosphate.
D) ribonucleoside triphosphate.
E) ribozyme.

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If the sequence of an RNA molecule is 5ʹ-GGCAUCGACG-3ʹ, what is the sequence of the nontemplate strand of DNA?


A) 5ʹ-GGCATCGACG-3ʹ
B) 3ʹ-GGCATCGACG-5ʹ
C) 5ʹ-CCGTAGCTGC-3ʹ
D) 3ʹ-CCGTAGCTGC-5ʹ
E) 3ʹ-CGTCGATGCC-5ʹ

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Which of the following statements is FALSE regarding TFIID?


A) It contains a TATA-binding protein.
B) It aids in initiation of transcription.
C) It binds to the core promoter.
D) It binds to the TATA box.
E) It is a transcriptional activator protein.

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Which of the following statements is NOT true?


A) Both DNA and RNA are synthesized in a 5' to 3' direction.
B) During RNA synthesis, the DNA template strand is read in a 3' to 5'direction.
C) During RNA synthesis, new nucleotides are added to the 3' end of the growing RNA molecule.
D) RNA polymerase has 5' to 3' polymerase activity.
E) RNA molecules have the same 5' to 3'orientation as the DNA template strands to which they are complementary.

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The following diagram represents a transcription unit. The following diagram represents a transcription unit.   What would likely happen to transcription of this transcription unit if a certain consensus sequence within region A is removed via deletion? A)  The mutation in region A would result in truncated RNA transcript that is shorter than expected RNA. B)  The mutation in region A does not affect the transcription as the transcript is copied only from regions B and C. C)  The transcript may get copied in reverse direction as the orientation of region A is important for the direction of the transcription. D)  The transcript may not be produced as the consensus sequence within region A may be important for the initiation of the transcription. E)  The transcription occurs normally as there are other consensus sequences that would compensate for the loss of one. What would likely happen to transcription of this transcription unit if a certain consensus sequence within region A is removed via deletion?


A) The mutation in region A would result in truncated RNA transcript that is shorter than expected RNA.
B) The mutation in region A does not affect the transcription as the transcript is copied only from regions B and C.
C) The transcript may get copied in reverse direction as the orientation of region A is important for the direction of the transcription.
D) The transcript may not be produced as the consensus sequence within region A may be important for the initiation of the transcription.
E) The transcription occurs normally as there are other consensus sequences that would compensate for the loss of one.

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Histone acetyltransferases add acetyl groups to lysines, which are positively charged amino acids. How might this affect the association of a nucleosome with DNA?

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Histone acetyltransferases (HATs) are en...

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