Question 1

The "permanent" part of adding wave in hair is due primarily to which of these actions?

Accepted Answer

A) rearrangement of hydrogen bonds between hair fibres 
B) reduction and re-oxidation of disulfide bonds in hair fibres 
C) reestablishment of new ionic interactions between hair fibres 
D) breaking and reforming peptide bonds in the hair polypeptides 
A) rearrangement of hydrogen bonds between hair fibres 
B) reduction and re-oxidation of disulfide bonds in hair fibres 
C) reestablishment of new ionic interactions between hair fibres 
D) breaking and reforming peptide bonds in the hair polypeptides

Question 2

Why should the core of most globular and membrane proteins consist almost entirely of α-helix and β-sheets?

Accepted Answer

A) Hydrogen bonded structures must be kept away from water solvent. 
B) Highly polar N-H and C=O moieties of the peptide backbone must be neutralized in the hydrophobic core of the protein. 
C) Hydrogen bonding occurs only in the core of proteins. 
D) Trapped water stabilizes the helix and sheet structures. 
A) Hydrogen bonded structures must be kept away from water solvent. 
B) Highly polar N-H and C=O moieties of the peptide backbone must be neutralized in the hydrophobic core of the protein. 
C) Hydrogen bonding occurs only in the core of proteins. 
D) Trapped water stabilizes the helix and sheet structures.

Question 3

Which compound(s)can be used at high concentrations to dampen out electrostatic interactions among amino acid residues?

Accepted Answer

A) water 
B) organic solvents 
C) salts 
D) heat 
A) water 
B) organic solvents 
C) salts 
D) heat

Question 4

How are the parallel β-sheets in a β-barrel connected?

Accepted Answer

A) by regions of α-helix 
B) by β-turns 
C) by electrostatic interactions 
D) by disulfide bonds 
A) by regions of α-helix 
B) by β-turns 
C) by electrostatic interactions 
D) by disulfide bonds

Question 5

Which of the following does the tertiary structure of proteins NOT depend on?

Accepted Answer

A) Protein structure depends on primary structure. 
B) Secondary structures form whenever possible. 
C) Proteins are stable as a single-layer structure. 
D) Peptide segments between secondary structures are short. 
A) Protein structure depends on primary structure. 
B) Secondary structures form whenever possible. 
C) Proteins are stable as a single-layer structure. 
D) Peptide segments between secondary structures are short.

Question 6

Which of the following does NOT apply to the collective motions of proteins?

Accepted Answer

A) The movements of groups of atoms are covalently linked in such a way that the group moves as a unit. 
B) It includes trypsin ring flips. 
C) It includes trans-cis isomerization of prolines. 
D) It involves the flexible antigen-binding domains of immunoglobulins. 
A) The movements of groups of atoms are covalently linked in such a way that the group moves as a unit. 
B) It includes trypsin ring flips. 
C) It includes trans-cis isomerization of prolines. 
D) It involves the flexible antigen-binding domains of immunoglobulins.

Question 7

Which of the following is NOT a characteristic of prolyl hydroxylase?

Accepted Answer

A) requires citric acid 
B) is activated by Fe2+ 
C) requires molecular oxygen 
D) requires a-ketoglutarate 
A) requires citric acid 
B) is activated by Fe2+ 
C) requires molecular oxygen 
D) requires a-ketoglutarate

Question 8

Which of these characteristics does NOT apply to a-keratin?

Accepted Answer

A) primary component in hair,claws,fingernails,and horns of animals 
B) consists of 4 helical strands arranged as twisted pairs of 2-stranded coiled coils 
C) has associated hydrophobic strips on the 2 coiled coils 
D) principal constituent of connective tissues in animals 
A) primary component in hair,claws,fingernails,and horns of animals 
B) consists of 4 helical strands arranged as twisted pairs of 2-stranded coiled coils 
C) has associated hydrophobic strips on the 2 coiled coils 
D) principal constituent of connective tissues in animals

Question 9

What is/are the primary stabilizer(s)of α-helices?

Accepted Answer

A) hydrogen bonds between the main-chain peptide bond component atoms 
B) hydrophobic interactions between the α-carbons of the main chain 
C) hydrogen bonding between the R groups 
D) hydrophobic interactions between R groups and the solvent water 
A) hydrogen bonds between the main-chain peptide bond component atoms 
B) hydrophobic interactions between the α-carbons of the main chain 
C) hydrogen bonding between the R groups 
D) hydrophobic interactions between R groups and the solvent water

Exam 6: Proteins: Secondary, tertiary, and Quaternary Structure

The "permanent" part of adding wave in hair is due primarily to which of these actions?

Why should the core of most globular and membrane proteins consist almost entirely of α-helix and β-sheets?

Which compound(s)can be used at high concentrations to dampen out electrostatic interactions among amino acid residues?

How are the parallel β-sheets in a β-barrel connected?

Which of the following does the tertiary structure of proteins NOT depend on?

Which of the following does NOT apply to the collective motions of proteins?

Which of the following is NOT a characteristic of prolyl hydroxylase?

Which of these characteristics does NOT apply to a-keratin?

What is/are the primary stabilizer(s)of α-helices?

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

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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