Question 1

The 28S, 18S and 5.8S forms of rRNA:

Accepted Answer

A)  are encoded by three distinct genetic loci that are coregulated. 
B)  are encoded by three distinct genetic loci that are differentially regulated according to requirements for each rRNA. 
C)  are encoded by a single genetic locus whose transcript is subsequently processed. 
D)  are encoded by a single genetic locus whose transcript is differentially amplified. 
E)  are the result of alternate splicing of a single transcript. 
A)  are encoded by three distinct genetic loci that are coregulated. 
B)  are encoded by three distinct genetic loci that are differentially regulated according to requirements for each rRNA. 
C)  are encoded by a single genetic locus whose transcript is subsequently processed. 
D)  are encoded by a single genetic locus whose transcript is differentially amplified. 
E)  are the result of alternate splicing of a single transcript.

Question 2

The polymerase that transcribes rRNA in eukaryotes is

Accepted Answer

A)  RNA polymerase I 
B)  RNA polymerase II 
C)  RNA polymerase III 
D)  DNA polymerase I 
E)  DNA polymerase III 
A)  RNA polymerase I 
B)  RNA polymerase II 
C)  RNA polymerase III 
D)  DNA polymerase I 
E)  DNA polymerase III

Question 3

How does the metabolism of rRNA differ from that of tRNA in eukaryotic cells?

Accepted Answer

A)  rRNA is cleaved from a larger precursor while tRNA is transcribed as such from the transfer RNA cistrons. 
B)  rRNA is made in the nucleus while tRNA is synthesized in the cytoplasm. 
C)  The methylated bases in rRNA are added at the polymer level while in tRNA these bases are incorporated as nucleoside triphosphates. 
D)  rRNA forms specific complexes with proteins in the nucleus while tRNA does not. 
A)  rRNA is cleaved from a larger precursor while tRNA is transcribed as such from the transfer RNA cistrons. 
B)  rRNA is made in the nucleus while tRNA is synthesized in the cytoplasm. 
C)  The methylated bases in rRNA are added at the polymer level while in tRNA these bases are incorporated as nucleoside triphosphates. 
D)  rRNA forms specific complexes with proteins in the nucleus while tRNA does not.

Question 4

A characteristic of transcription by RNA polymerase II in eukaryotic cells is:

Accepted Answer

A)  the absence of promoters elements. 
B)  translation initiation prior to transcription termination. 
C)  translation termination prior to transcription termination. 
D)  covalent addition of nucleotide(s) that are not encoded by DNA to the 5' and 3' ends of the transcript. 
E)  constitutive expression of most genes. 
A)  the absence of promoters elements. 
B)  translation initiation prior to transcription termination. 
C)  translation termination prior to transcription termination. 
D)  covalent addition of nucleotide(s) that are not encoded by DNA to the 5' and 3' ends of the transcript. 
E)  constitutive expression of most genes.

Question 5

Splice site recognition is determined, in part, by:

Accepted Answer

A)  DNA polymerase. 
B)  RNA polymerase. 
C)  invariant sequences at the 5' and 3' ends of exons. 
D)  invariant sequences at the 5' and 3' ends of introns. 
E)  base_pairing between adjacent introns. 
A)  DNA polymerase. 
B)  RNA polymerase. 
C)  invariant sequences at the 5' and 3' ends of exons. 
D)  invariant sequences at the 5' and 3' ends of introns. 
E)  base_pairing between adjacent introns.

Question 6

An enzyme which is the most useful in the synthesis of a complementary copy of an RNA molecule is

Accepted Answer

A)  DNA polymerase III. 
B)  DNA polymerase I. 
C)  RNA polymerase. 
D)  reverse transcriptase. 
E)  poly A polymerase. 
A)  DNA polymerase III. 
B)  DNA polymerase I. 
C)  RNA polymerase. 
D)  reverse transcriptase. 
E)  poly A polymerase.

Question 7

Eukaryotic RNA polymerase II differs from the prokaryotic RNA polymerase because it

Accepted Answer

A)  retains sigma factor during elongation. 
B)  can incorporate either deoxy_ or ribonucleotide precursors. 
C)  requires multiple accessory proteins. 
D)  transcribes only ribosomal RNA genes. 
E)  interacts directly with the termination factor rho. 
A)  retains sigma factor during elongation. 
B)  can incorporate either deoxy_ or ribonucleotide precursors. 
C)  requires multiple accessory proteins. 
D)  transcribes only ribosomal RNA genes. 
E)  interacts directly with the termination factor rho.

Question 8

A eukaryotic cell unable to synthesize small nuclear RNA (snRNA) would

Accepted Answer

A)  be unable to process tRNA precursors. 
B)  be unable to splice mRNA precursors. 
C)  have defective ribosomes. 
D)  be unable to initiate RNA synthesis at the proper sites. 
A)  be unable to process tRNA precursors. 
B)  be unable to splice mRNA precursors. 
C)  have defective ribosomes. 
D)  be unable to initiate RNA synthesis at the proper sites.

Question 9

Intervening sequences (introns) are

Accepted Answer

A)  found in cDNA clones. 
B)  only found in eukaryotic DNA. 
C)  removed during DNA replication. 
D)  found in genomic DNA and hnRNA. 
E)  added to mRNA by the spliceosome. 
A)  found in cDNA clones. 
B)  only found in eukaryotic DNA. 
C)  removed during DNA replication. 
D)  found in genomic DNA and hnRNA. 
E)  added to mRNA by the spliceosome.

Question 10

Which statement about introns is correct? Introns are:

Accepted Answer

A)  noncoding sequences which interrupt the coding sequences of genes. 
B)  nontranscribed sequences which interrupt the transcribed sequences of genes. 
C)  regulatory elements which determine the efficiency of transcription. 
D)  common to the genes of all organisms. 
E)  unstable genetic elements which transpose randomly throughout the genome. 
A)  noncoding sequences which interrupt the coding sequences of genes. 
B)  nontranscribed sequences which interrupt the transcribed sequences of genes. 
C)  regulatory elements which determine the efficiency of transcription. 
D)  common to the genes of all organisms. 
E)  unstable genetic elements which transpose randomly throughout the genome.

Question 11

Splicing of eukaryotic mRNA precursors involves all of the following EXCEPT

Accepted Answer

A)  binding of small nuclear RNAs. 
B)  binding of poly(
A)  polymerase. 
C)  assembly of spliceosome. 
D)  RNA cleavage and ligation reactions. 
A)  binding of small nuclear RNAs. 
B)  binding of poly(
A)  polymerase. 
C)  assembly of spliceosome. 
D)  RNA cleavage and ligation reactions.

Question 12

Which of the following is composed of 4 different species in eukaryotic cells?

Accepted Answer

A)  tRNA 
B)  mRNA 
C)  rRNA 
D)  all of the above 
E)  none of the above 
A)  tRNA 
B)  mRNA 
C)  rRNA 
D)  all of the above 
E)  none of the above

Question 13

How are most of the RNA species in ribosomes synthesized?

Accepted Answer

A)  by selective degradation of a single, large RNA molecule 
B)  on one of the ribosomal subunits 
C)  by condensation of two or more mRNA species 
D)  by translation of mRNA 
A)  by selective degradation of a single, large RNA molecule 
B)  on one of the ribosomal subunits 
C)  by condensation of two or more mRNA species 
D)  by translation of mRNA

Question 14

Transcription of the major fraction of ribosomal RNA in eukaryotic cells

Accepted Answer

A)  occurs in the nucleoplasm, outside of the nucleolus. 
B)  involves transcription from a gene which occurs twice in a diploid cell. 
C)  leads to a large precursor which is processed by methylation and cleavage. 
D)  would be inhibited by puromycin but not by actinomycin D 
E)  none of the above. 
A)  occurs in the nucleoplasm, outside of the nucleolus. 
B)  involves transcription from a gene which occurs twice in a diploid cell. 
C)  leads to a large precursor which is processed by methylation and cleavage. 
D)  would be inhibited by puromycin but not by actinomycin D 
E)  none of the above.

Question 15

Some small nuclear ribonucleoprotein complexes are involved in

Accepted Answer

A)  adding a 5' cap. 
B)  splicing. 
C)  signal peptide recognition. 
D)  polyadenylation. 
E)  translation initiation. 
A)  adding a 5' cap. 
B)  splicing. 
C)  signal peptide recognition. 
D)  polyadenylation. 
E)  translation initiation.

Question 16

During the formation of rRNA from the 45S precursor in animal cells

Accepted Answer

A)  all methylated nucleotides are removed. 
B)  all methylated nucleotides are added only after the formation of the ribosomal particles. 
C)  essentially all methylated nucleotides are conserved. 
D)  no methylated nucleotides occur in rRNA. 
A)  all methylated nucleotides are removed. 
B)  all methylated nucleotides are added only after the formation of the ribosomal particles. 
C)  essentially all methylated nucleotides are conserved. 
D)  no methylated nucleotides occur in rRNA.

Question 17

With regard to RNA polymerases of eukaryotic cells

Accepted Answer

A)  polymerase I activity is highly sensitive to inhibition by alpha-amanitin. 
B)  polymerase II is localized primarily in the nucleolus. 
C)  polymerase III is responsible for tRNA and 5S ribosomal RNA synthesis. 
D)  polymerase I is localized primarily in the nucleoplasm. 
E)  polymerase II is responsible for 18S and 28S ribosomal RNA synthesis. 
A)  polymerase I activity is highly sensitive to inhibition by alpha-amanitin. 
B)  polymerase II is localized primarily in the nucleolus. 
C)  polymerase III is responsible for tRNA and 5S ribosomal RNA synthesis. 
D)  polymerase I is localized primarily in the nucleoplasm. 
E)  polymerase II is responsible for 18S and 28S ribosomal RNA synthesis.

Question 18

Which of the following best describes the role of sigma factor in RNA synthesis?

Accepted Answer

A)  Sigma factor is essential for elongation. 
B)  Sigma factor is responsible for the recognition of specific initiation sites on a DNA template. 
C)  Sigma factor is responsible for separation of DNA strands. 
D)  Sigma factor is responsible for releasing the completed chain. 
A)  Sigma factor is essential for elongation. 
B)  Sigma factor is responsible for the recognition of specific initiation sites on a DNA template. 
C)  Sigma factor is responsible for separation of DNA strands. 
D)  Sigma factor is responsible for releasing the completed chain.

Exam 5: RNA: Transcription and Rna Processing

The 28S, 18S and 5.8S forms of rRNA:

The polymerase that transcribes rRNA in eukaryotes is

How does the metabolism of rRNA differ from that of tRNA in eukaryotic cells?

A characteristic of transcription by RNA polymerase II in eukaryotic cells is:

Splice site recognition is determined, in part, by:

An enzyme which is the most useful in the synthesis of a complementary copy of an RNA molecule is

Eukaryotic RNA polymerase II differs from the prokaryotic RNA polymerase because it

A eukaryotic cell unable to synthesize small nuclear RNA (snRNA) would

Intervening sequences (introns) are

Which statement about introns is correct? Introns are:

Splicing of eukaryotic mRNA precursors involves all of the following EXCEPT

Which of the following is composed of 4 different species in eukaryotic cells?

How are most of the RNA species in ribosomes synthesized?

Transcription of the major fraction of ribosomal RNA in eukaryotic cells

Some small nuclear ribonucleoprotein complexes are involved in

During the formation of rRNA from the 45S precursor in animal cells

With regard to RNA polymerases of eukaryotic cells

Which of the following best describes the role of sigma factor in RNA synthesis?

Eukaryotic Cell Structure

DNA and RNA: Composition and Structure

Protein I: Composition and Structure

DNA Replication, Recombination, and Repair

Protein Synthesis: Translation and Posttranslational Modifications

Recombinant Dna and Biotechnology

Regulation of Gene Expression

Protein II: Structure-Function Relationships in Protein Families

Enzymes: Classification, Kinetics, and Control

The Cytochromes P450 and Nitric Oxide Synthases

Biological Membranes: Structure and Membrane Transport

Fundamentals of Signal Transduction

Bioenergetics and Oxidative Metabolism

Carbohydrate Metabolism I: Major Metabolic Pathways and Their Control

Carbohydrate Metabolism II: Special Pathways and Glycoconjugates

Lipid Metabolism I: Synthesis, Storage, and Utilization of Fatty Acids and Triacylglycerols

Lipid Metabolism II: Pathways of Metabolism of Special Lipids

Amino Acid Metabolism

Purine and Pyrimidine Nucleotide Metabolism

Metabolic Interrelationships

Biochemistry of Hormones

Molecular Cell Biology

Cell Cycle, Programmed Cell Death, and Cancer

Digestion and Absorption of Basic Nutritional Constituents

Digestion and Absorption of Basic Nutritional Constituents

Principles of Nutrition I and II

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