Question 1

Which of the following is now the most commonly used technique for finding the sequence of proteins?

Accepted Answer

A) chemical sequencing 
B) mass spectrometry 
C) HPLC 
D) gene transcription and translation 
A) chemical sequencing 
B) mass spectrometry 
C) HPLC 
D) gene transcription and translation

Question 2

Insulin is a polypeptide hormone that contains 2 short polypeptide chains linked by 2 interstrand disulfide bonds.Which of the following treatments would NOT be useful for determining its primary structure?

Accepted Answer

A) reduction of the peptides with SDS 
B) sequencing of the peptides with Edman chemistry 
C) separation of the peptides by chromatography techniques 
D) alkylation of the peptides with iodoacetate 
A) reduction of the peptides with SDS 
B) sequencing of the peptides with Edman chemistry 
C) separation of the peptides by chromatography techniques 
D) alkylation of the peptides with iodoacetate

Question 3

Which of the following tproteins do not perform any obvious chemical transformation,but control the ability of other proteins to carry out their physiological functions?

Accepted Answer

A) regulatory 
B) transport 
C) storage 
D) structural 
A) regulatory 
B) transport 
C) storage 
D) structural

Question 4

Which of the following techniques is used for protein isolation and purification?

Accepted Answer

A) ion exchange chromatography 
B) Edman degradation 
C) PCR 
D) gas-liquid chromatography 
A) ion exchange chromatography 
B) Edman degradation 
C) PCR 
D) gas-liquid chromatography

Question 5

Which of the following factors is NOT considered a level of protein structure?

Accepted Answer

A) the interaction between subunits of a protein 
B) the order of amino acid residues in the peptide chain 
C) the 3-dimensional arrangement of all atoms in a single peptide 
D) the hydrogen bond arrangement of nonpolar R-groups 
A) the interaction between subunits of a protein 
B) the order of amino acid residues in the peptide chain 
C) the 3-dimensional arrangement of all atoms in a single peptide 
D) the hydrogen bond arrangement of nonpolar R-groups

Question 6

Which of the following best defines a gene?

Accepted Answer

A) a segment of DNA nucleotide bases that encode for the synthesis of a particular protein 
B) a single strand of DNA that is designated as the sense strand 
C) a functional segment of a unique protein 
D) the segment of DNA that is changed in a mutation 
A) a segment of DNA nucleotide bases that encode for the synthesis of a particular protein 
B) a single strand of DNA that is designated as the sense strand 
C) a functional segment of a unique protein 
D) the segment of DNA that is changed in a mutation

Question 7

Which of the following is a property common to fibrous proteins?

Accepted Answer

A) They are highly soluble in water. 
B) Their hydrophilic residues are directed into the interior of the protein. 
C) They exhibit enzymatic activity. 
D) They serve structural roles in cells. 
A) They are highly soluble in water. 
B) Their hydrophilic residues are directed into the interior of the protein. 
C) They exhibit enzymatic activity. 
D) They serve structural roles in cells.

Question 8

Which of the following is a feature of membrane proteins?

Accepted Answer

A) They have membrane-associated amino acids with polar side chains. 
B) They are much more soluble in detergents than in water. 
C) They have hydrophobic amino acids that are oriented inward. 
D) They have a globular structure. 
A) They have membrane-associated amino acids with polar side chains. 
B) They are much more soluble in detergents than in water. 
C) They have hydrophobic amino acids that are oriented inward. 
D) They have a globular structure.

Question 9

Which level of structural organization best describes the amino acid sequence of a protein?

Accepted Answer

A) primary 
B) secondary 
C) tertiary 
D) quaternary 
A) primary 
B) secondary 
C) tertiary 
D) quaternary

Question 10

Which of the following factors determines a protein's particular conformation?

Accepted Answer

A) the overall 2-dimensional architecture of the protein 
B) the breaking and reforming of covalent bonds 
C) the rotations about every second bond along the peptide backbone 
D) the amino acid side-chain interactions 
A) the overall 2-dimensional architecture of the protein 
B) the breaking and reforming of covalent bonds 
C) the rotations about every second bond along the peptide backbone 
D) the amino acid side-chain interactions

Question 11

Which level of structural organization best describes the a-helix and b-strand components of protein structure?

Accepted Answer

A) primary 
B) secondary 
C) tertiary 
D) quaternary 
A) primary 
B) secondary 
C) tertiary 
D) quaternary

Question 12

Suppose that the peptide Ala-Met-Lys-Ser is reacted with phenylisothiocyanate at pH 8.0,followed by mild acidification,which is the first cycle of Edman method? Which of the following would be released?

Accepted Answer

A) the labelled peptide Ala-Met-Lys-Ser-PTH 
B) PTH-Ala,PTH-Ser,PTH-Lys,and PTH-Met 
C) PTH-Ser and the peptide Ala-Met-Lys 
D) PTH-Ala and the peptide Met-Lys-Ser 
A) the labelled peptide Ala-Met-Lys-Ser-PTH 
B) PTH-Ala,PTH-Ser,PTH-Lys,and PTH-Met 
C) PTH-Ser and the peptide Ala-Met-Lys 
D) PTH-Ala and the peptide Met-Lys-Ser

Question 13

Which structural classification best describes glutamine synthetase found in E.coli?

Accepted Answer

A) monomer 
B) heterotrimer 
C) homomultimer 
D) heteromultimer 
A) monomer 
B) heterotrimer 
C) homomultimer 
D) heteromultimer

Question 14

Which of the following characteristics about the peptide Lys-Met-Cys-Phe-Ala-Trp is correct?

Accepted Answer

A) It has a molecular weight around 700 kDa and shows a strong absorption band at 280 nm. 
B) Treatment with carboxypeptidase results in lysine and a peptide. 
C) Trypsin digestion produces an amino acid and a pentapeptide with Met on the amino end. 
D) Chymotrypsin digestion yields 2 tripeptides. 
A) It has a molecular weight around 700 kDa and shows a strong absorption band at 280 nm. 
B) Treatment with carboxypeptidase results in lysine and a peptide. 
C) Trypsin digestion produces an amino acid and a pentapeptide with Met on the amino end. 
D) Chymotrypsin digestion yields 2 tripeptides.

Question 15

Which of the following treatments is NOT a useful method for dissociating a heteromultimeric protein during sequencing?

Accepted Answer

A) high salt concentrations 
B) 6 N HCl at 110°C for 24 hours 
C) 8 M urea 
D) 6 M guanidinium chloride 
A) high salt concentrations 
B) 6 N HCl at 110°C for 24 hours 
C) 8 M urea 
D) 6 M guanidinium chloride

Question 16

Which of the following products are formed from the acid hydrolysis of a simple amide?

Accepted Answer

A) aldehyde and alcohol 
B) acid and amine 
C) ester and alcohol 
D) amine and aldehyde 
A) aldehyde and alcohol 
B) acid and amine 
C) ester and alcohol 
D) amine and aldehyde

Question 17

Which of the following is a characteristic of homologous proteins from different organisms?

Accepted Answer

A) They have very little sequence similarity with other proteins with similar function. 
B) They have nearly identical lengths. 
C) They do not share a significant degree of sequence similarity. 
D) They have sequence similarity indirectly correlated to the relatedness of the species from which they were derived. 
A) They have very little sequence similarity with other proteins with similar function. 
B) They have nearly identical lengths. 
C) They do not share a significant degree of sequence similarity. 
D) They have sequence similarity indirectly correlated to the relatedness of the species from which they were derived.

Question 18

Suppose a protein is treated with trypsin.Which of the following techniques could be used to determine its identity by peptide mass fingerprinting?

Accepted Answer

A) NMR 
B) MALDI-TOF mass spectrometry 
C) HPLC 
D) gel electrophoresis 
A) NMR 
B) MALDI-TOF mass spectrometry 
C) HPLC 
D) gel electrophoresis

Question 19

Which of the following protein terms describes hemoglobin?

Accepted Answer

A) regulatory 
B) transport 
C) storage 
D) structural 
A) regulatory 
B) transport 
C) storage 
D) structural

Question 20

The formation of a disulfide bond is an example of what level(s)of protein structure?

Accepted Answer

A) primary and secondary 
B) secondary and tertiary 
C) tertiary and quaternary 
D) quaternary 
A) primary and secondary 
B) secondary and tertiary 
C) tertiary and quaternary 
D) quaternary

Exam 5: Proteins: Their Primary Structure and Biological Functions

Which of the following is now the most commonly used technique for finding the sequence of proteins?

Insulin is a polypeptide hormone that contains 2 short polypeptide chains linked by 2 interstrand disulfide bonds.Which of the following treatments would NOT be useful for determining its primary structure?

Which of the following tproteins do not perform any obvious chemical transformation,but control the ability of other proteins to carry out their physiological functions?

Which of the following techniques is used for protein isolation and purification?

Which of the following factors is NOT considered a level of protein structure?

Which of the following best defines a gene?

Which of the following is a property common to fibrous proteins?

Which of the following is a feature of membrane proteins?

Which level of structural organization best describes the amino acid sequence of a protein?

Which of the following factors determines a protein's particular conformation?

Which level of structural organization best describes the a-helix and b-strand components of protein structure?

Suppose that the peptide Ala-Met-Lys-Ser is reacted with phenylisothiocyanate at pH 8.0,followed by mild acidification,which is the first cycle of Edman method? Which of the following would be released?

Which structural classification best describes glutamine synthetase found in E.coli?

Which of the following characteristics about the peptide Lys-Met-Cys-Phe-Ala-Trp is correct?

Which of the following treatments is NOT a useful method for dissociating a heteromultimeric protein during sequencing?

Which of the following products are formed from the acid hydrolysis of a simple amide?

Which of the following is a characteristic of homologous proteins from different organisms?

Suppose a protein is treated with trypsin.Which of the following techniques could be used to determine its identity by peptide mass fingerprinting?

Which of the following protein terms describes hemoglobin?

The formation of a disulfide bond is an example of what level(s)of protein structure?

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

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids

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

Structure of 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

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