Question 1

Which of the following do phylogenetic comparisons of secondary structures of rRNAs from a variety of species reveal?

Accepted Answer

A) strikingly similar structures and a high degree of similarity in the nucleotide sequences of the rRNAs themselves 
B) strikingly similar structures and a low degree of similarity in the nucleotide sequences of the rRNAs themselves 
C) dissimilar structures and a high degree of similarity in the nucleotide sequences of the rRNAs themselves 
D) dissimilar structures and a low degree of similarity in the nucleotide sequences of the rRNAs themselves 
A) strikingly similar structures and a high degree of similarity in the nucleotide sequences of the rRNAs themselves 
B) strikingly similar structures and a low degree of similarity in the nucleotide sequences of the rRNAs themselves 
C) dissimilar structures and a high degree of similarity in the nucleotide sequences of the rRNAs themselves 
D) dissimilar structures and a low degree of similarity in the nucleotide sequences of the rRNAs themselves

Question 2

Which of the following is the nucleotide sequence of the DNA strand that is complementary to 5'-ATCGCAACTGTCACTA-3'?

Accepted Answer

A) 5'-TAGCGTTGACAGTGAT-3' 
B) 5'-UAGUGACAGUUGCGAU-3' 
C) 5'-ATCACTGTCAACGCTA-3' 
D) 5'-TAGTGACAGTTGCGAT-3' 
A) 5'-TAGCGTTGACAGTGAT-3' 
B) 5'-UAGUGACAGUUGCGAU-3' 
C) 5'-ATCACTGTCAACGCTA-3' 
D) 5'-TAGTGACAGTTGCGAT-3'

Question 3

Which of the following features of DNA is analogous to twisting or untwisting a 2-stranded rope so that it is torsionally stressed?

Accepted Answer

A) b-sheet 
B) hairpin turn 
C) cloverleaf 
D) supercoiling 
A) b-sheet 
B) hairpin turn 
C) cloverleaf 
D) supercoiling

Question 4

Which of the following is a characteristic of DNA polymerase?

Accepted Answer

A) copies the sequence of nucleotides of one strand in a complementary fashion 
B) requires a primer with a free 5'-OH end,but the 3'-end may be phosphorylated 
C) copies the sequence of nucleotides of one strand to form two new strands 
D) synthesizes new strands by adding successive nucleotides in the 3'?5' direction 
A) copies the sequence of nucleotides of one strand in a complementary fashion 
B) requires a primer with a free 5'-OH end,but the 3'-end may be phosphorylated 
C) copies the sequence of nucleotides of one strand to form two new strands 
D) synthesizes new strands by adding successive nucleotides in the 3'?5' direction

Question 5

Which of the following is a characteristic of the chain termination protocol?

Accepted Answer

A) One dNTP is a radioactively labelled tracer to detect the products in the polymerization process. 
B) An unknown sequence serves as a template in a polymerization reaction. 
C) Two parallel reactions are run,each containing the substrates for DNA polymerase. 
D) The chain is terminated where the dideoxynucleotide is incorporated. 
A) One dNTP is a radioactively labelled tracer to detect the products in the polymerization process. 
B) An unknown sequence serves as a template in a polymerization reaction. 
C) Two parallel reactions are run,each containing the substrates for DNA polymerase. 
D) The chain is terminated where the dideoxynucleotide is incorporated.

Question 6

Which of the following conformations do double-helical DNA:RNA hybrids and double-stranded regions of RNA chains often assume?

Accepted Answer

A) A-like conformation 
B) B-like conformation 
C) Z-like conformation 
D) triple-helix conformation 
A) A-like conformation 
B) B-like conformation 
C) Z-like conformation 
D) triple-helix conformation

Question 7

Sequencing nucleic acids is now easier than sequencing polypeptides.Which of the following developed technologies facilitates this?

Accepted Answer

A) restriction endonucleases and polyacrylamide gel electrophoresis 
B) base-specific chemical cleavage and autoradiography 
C) cytosine methylation and base-specific chemical cleavage 
D) double-helix denaturation and restriction endonucleases 
A) restriction endonucleases and polyacrylamide gel electrophoresis 
B) base-specific chemical cleavage and autoradiography 
C) cytosine methylation and base-specific chemical cleavage 
D) double-helix denaturation and restriction endonucleases

Question 8

Which of the following is a characteristic of DNA gyrase in E.coli?

Accepted Answer

A) It hydrolyzes GTP during its reaction mechanism. 
B) It cuts only one strand of a dsDNA. 
C) It is classified as a topoisomerase. 
D) It works to induce positive supercoiling in DNA. 
A) It hydrolyzes GTP during its reaction mechanism. 
B) It cuts only one strand of a dsDNA. 
C) It is classified as a topoisomerase. 
D) It works to induce positive supercoiling in DNA.

Question 9

Which of the following is NOT a property of nucleosomes?

Accepted Answer

A) protein spools neatly wrapped with DNA 
B) fundamental structural unit in chromatin 
C) protein spools made up of single histones H2A,H2B,H3,and H4 octameric aggregates 
D) DNA binding of histones by ionic bonds of positively charged amino acids and the negatively charged phosphate groups 
A) protein spools neatly wrapped with DNA 
B) fundamental structural unit in chromatin 
C) protein spools made up of single histones H2A,H2B,H3,and H4 octameric aggregates 
D) DNA binding of histones by ionic bonds of positively charged amino acids and the negatively charged phosphate groups

Exam 25: Structure of Nucleic Acids

Which of the following do phylogenetic comparisons of secondary structures of rRNAs from a variety of species reveal?

Which of the following is the nucleotide sequence of the DNA strand that is complementary to 5'-ATCGCAACTGTCACTA-3'?

Which of the following features of DNA is analogous to twisting or untwisting a 2-stranded rope so that it is torsionally stressed?

Which of the following is a characteristic of DNA polymerase?

Which of the following is a characteristic of the chain termination protocol?

Which of the following conformations do double-helical DNA:RNA hybrids and double-stranded regions of RNA chains often assume?

Sequencing nucleic acids is now easier than sequencing polypeptides.Which of the following developed technologies facilitates this?

Which of the following is a characteristic of DNA gyrase in E.coli?

Which of the following is NOT a property of nucleosomes?

The Facts of Life: Chemistry Is the Logic of Biological Phenomena

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, tertiary, and Quaternary Structure

Carbohydrates and the Glycoconjugates of Cell Surfaces

Lipids

Lipid Biosynthesis

Membranes and Membrane Transport

The Reception and Transmission of Extracellular Information

Enzymes Kinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Nutrition and the Organization of Metabolism

Glycolysis

The Tricarboxylic Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Gluconeogenesis, glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Nitrogen Acquisition and Amino Acid Metabolism

Nucleotides and Nucleic Acids

Synthesis and Degradation of Nucleotides

Recombinant Dna: Cloning and Creation of Chimeric Genes

DNA Metabolism: Replication, recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

Post-Transcriptional Regulation of Gene Expression

Completing the Protein Life Cycle: Folding, processing, and Degradation

Metabolic Integration and Organ Specialization

Filters