Question 1

The following amino acid is classified as nonpolar. Which of the following statements best describes why it is classified this way?

Accepted Answer

A)  It does not form a zwitterion. 
B)  It is neutral at physiological pH. 
C)  Its side chain is not charged at physiological pH. 
D)  Its side chain contains only an alkyl group. 
E)  This amino acid is soluble only in nonpolar solvents. 
A)  It does not form a zwitterion. 
B)  It is neutral at physiological pH. 
C)  Its side chain is not charged at physiological pH. 
D)  Its side chain contains only an alkyl group. 
E)  This amino acid is soluble only in nonpolar solvents.

Question 2

Which of the following amino acids contain a thiol?

Accepted Answer

A)  tyrosine 
B)  histidine 
C)  threonone 
D)  cysteine 
E)  serine 
A)  tyrosine 
B)  histidine 
C)  threonone 
D)  cysteine 
E)  serine

Question 3

Which of the following biomolecules has the most diverse functions in the body?

Accepted Answer

A)  carbohydrates 
B)  proteins 
C)  nucleic acids 
D)  lipids 
E)  These have equally diverse functions. 
A)  carbohydrates 
B)  proteins 
C)  nucleic acids 
D)  lipids 
E)  These have equally diverse functions.

Question 4

Which of the following statements about enzyme names is FALSE?

Accepted Answer

A)  Enzymes are often named after the type of reaction that they catalyze or their substrate. 
B)  Enzyme names almost always include the name of any cofactors involved in their reaction. 
C)  Enzyme names often have -ase at the end of them. 
D)  Some enzymes are named after where they were isolated from. 
E)  Enzyme names are typically italicized. 
A)  Enzymes are often named after the type of reaction that they catalyze or their substrate. 
B)  Enzyme names almost always include the name of any cofactors involved in their reaction. 
C)  Enzyme names often have -ase at the end of them. 
D)  Some enzymes are named after where they were isolated from. 
E)  Enzyme names are typically italicized.

Question 5

Which type of protein can be used for energy when necessary?

Accepted Answer

A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins 
A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins

Question 6

Not all proteins have this level of protein architecture.

Accepted Answer

A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary 
A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary

Question 7

Which of the following occur when a protein is denatured? 
II. Covalent bonds are broken.
III. Hydrogen bonds are broken.
IV. The protein loses its shape.
V. The protein loses its biological activity.

Accepted Answer

A)  All of these are true statements. 
B)  All of these statements, except IV, are true. 
C)  All of these statements, except I, are true. 
D)  Only II and III are true. 
E)  None of these statements is true. 
A)  All of these are true statements. 
B)  All of these statements, except IV, are true. 
C)  All of these statements, except I, are true. 
D)  Only II and III are true. 
E)  None of these statements is true.

Question 8

Which of the following statements best defines an essential amino acid?

Accepted Answer

A)  It is an amino acid that is necessary for life. 
B)  It is an amino acid that is synthesized in the body. 
C)  It is any of the 20 amino acids. 
D)  It is another name for the nonpolar amino acids. 
E)  It is an amino acid that cannot be produced by the body. 
A)  It is an amino acid that is necessary for life. 
B)  It is an amino acid that is synthesized in the body. 
C)  It is any of the 20 amino acids. 
D)  It is another name for the nonpolar amino acids. 
E)  It is an amino acid that cannot be produced by the body.

Question 9

When two amino acids react to form a peptide bond, what new functional group is created?

Accepted Answer

A)  an alcohol 
B)  an amine 
C)  an amide 
D)  an ester 
E)  a phosphoester 
A)  an alcohol 
B)  an amine 
C)  an amide 
D)  an ester 
E)  a phosphoester

Question 10

According to the following graph of activity as a function of pH, at which of the following pHs is the reaction that pepsin catalyzes the fastest?

Accepted Answer

A)  1.0 
B)  2.0 
C)  5.0 
D)  7.0 
E)  11 
A)  1.0 
B)  2.0 
C)  5.0 
D)  7.0 
E)  11

Question 11

Which of the following statements best describes the purpose of a catalyst in a chemical reaction?

Accepted Answer

A)  The purpose of a catalyst is to speed up the rate of the reaction. 
B)  The purpose of a catalyst is to lower the energy of the reactants. 
C)  The purpose of a catalyst is to slow down the rate of the reaction. 
D)  The purpose of a catalyst is to lower the energy of the products. 
E)  The purpose of a catalyst is to increase the activation energy of the reaction. 
A)  The purpose of a catalyst is to speed up the rate of the reaction. 
B)  The purpose of a catalyst is to lower the energy of the reactants. 
C)  The purpose of a catalyst is to slow down the rate of the reaction. 
D)  The purpose of a catalyst is to lower the energy of the products. 
E)  The purpose of a catalyst is to increase the activation energy of the reaction.

Question 12

Which of the following structures illustrates an amino acid at physiological pH?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 13

What percentage of amino acids in sickle cell hemoglobin is different from normal hemoglobin?

Accepted Answer

A)  100% 
B)  50% 
C)  25% 
D)  10% 
E)  <1% 
A)  100% 
B)  50% 
C)  25% 
D)  10% 
E)  <1%

Question 14

Aspartic acid has a side chain that contains a carboxylic acid. At physiological pH, what do you expect the structure of aspartic acid to look like?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 15

At low pH, the amino acid zwitterion reacts with hydronium (H3O+). What is the product of this acid-base reaction?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 16

The structure of myoglobin is shown below. Myoglobin contains which of the following components?     I. α-helices
II) β-pleated sheets
III) a prosthetic group

Accepted Answer

A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  I and III 
A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  I and III

Question 17

Which of the following types of proteins provides physical support to tissues?

Accepted Answer

A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins 
A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins

Question 18

Which of the following choices are the best labels for this amino acid?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 19

Hemoglobin is an example of this type of protein.

Accepted Answer

A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins 
A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins

Question 20

In order to break a disulfide bond, what type of reaction occurs?

Accepted Answer

A)  an oxidation 
B)  a hydration 
C)  a dehydration 
D)  a reduction 
E)  an esterification 
A)  an oxidation 
B)  a hydration 
C)  a dehydration 
D)  a reduction 
E)  an esterification

The following amino acid is classified as nonpolar. Which of the following statements best describes why it is classified this way?

Which of the following amino acids contain a thiol?

Which of the following biomolecules has the most diverse functions in the body?

Which of the following statements about enzyme names is FALSE?

Which type of protein can be used for energy when necessary?

Not all proteins have this level of protein architecture.

Which of the following occur when a protein is denatured? II. Covalent bonds are broken. III. Hydrogen bonds are broken. IV. The protein loses its shape. V. The protein loses its biological activity.

Which of the following statements best defines an essential amino acid?

When two amino acids react to form a peptide bond, what new functional group is created?

According to the following graph of activity as a function of pH, at which of the following pHs is the reaction that pepsin catalyzes the fastest?

Which of the following statements best describes the purpose of a catalyst in a chemical reaction?

Which of the following structures illustrates an amino acid at physiological pH?

What percentage of amino acids in sickle cell hemoglobin is different from normal hemoglobin?

Aspartic acid has a side chain that contains a carboxylic acid. At physiological pH, what do you expect the structure of aspartic acid to look like?

At low pH, the amino acid zwitterion reacts with hydronium (H₃O⁺). What is the product of this acid-base reaction?

The structure of myoglobin is shown below. Myoglobin contains which of the following components? I. α-helices II) β-pleated sheets III) a prosthetic group

Which of the following types of proteins provides physical support to tissues?

Which of the following choices are the best labels for this amino acid?

Hemoglobin is an example of this type of protein.

In order to break a disulfide bond, what type of reaction occurs?

Measuring Matter and Energy

Atomic Structure and Nuclear Radiation

Compounds and Molecules

Chemical Quantities and Chemical Reactions

Changes of State and the Gas Laws

Organic Chemistry: Hydrocarbons

Organic Chemistry and Biomolecules

Solutions, Colloids and Membranes

Acids and Bases

The Reactions of Organic Functional Groups in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

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Exam 13: Proteins: Structure and Function

The following amino acid is classified as nonpolar. Which of the following statements best describes why it is classified this way?

Which of the following amino acids contain a thiol?

Which of the following biomolecules has the most diverse functions in the body?

Which of the following statements about enzyme names is FALSE?

Which type of protein can be used for energy when necessary?

Not all proteins have this level of protein architecture.

Which of the following occur when a protein is denatured? II. Covalent bonds are broken. III. Hydrogen bonds are broken. IV. The protein loses its shape. V. The protein loses its biological activity.

Which of the following statements best defines an essential amino acid?

When two amino acids react to form a peptide bond, what new functional group is created?

According to the following graph of activity as a function of pH, at which of the following pHs is the reaction that pepsin catalyzes the fastest?

Which of the following statements best describes the purpose of a catalyst in a chemical reaction?

Which of the following structures illustrates an amino acid at physiological pH?

What percentage of amino acids in sickle cell hemoglobin is different from normal hemoglobin?

Aspartic acid has a side chain that contains a carboxylic acid. At physiological pH, what do you expect the structure of aspartic acid to look like?

At low pH, the amino acid zwitterion reacts with hydronium (H3O+). What is the product of this acid-base reaction?

The structure of myoglobin is shown below. Myoglobin contains which of the following components? I. α-helices II) β-pleated sheets III) a prosthetic group

Which of the following types of proteins provides physical support to tissues?

Which of the following choices are the best labels for this amino acid?

Hemoglobin is an example of this type of protein.

In order to break a disulfide bond, what type of reaction occurs?

Measuring Matter and Energy

Atomic Structure and Nuclear Radiation

Compounds and Molecules

Chemical Quantities and Chemical Reactions

Changes of State and the Gas Laws

Organic Chemistry: Hydrocarbons

Organic Chemistry and Biomolecules

Solutions, Colloids and Membranes

Acids and Bases

The Reactions of Organic Functional Groups in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

Filters

At low pH, the amino acid zwitterion reacts with hydronium (H₃O⁺). What is the product of this acid-base reaction?