Question 1

Below is a graph of enzyme activity as a function of pH.Given the information on this graph, where is pepsin most likely to be found?

Accepted Answer

A)  stomach (pH 2) 
B)  liver (pH 5) 
C)  pancreas (pH 7) 
D)  blood (pH 7.4) 
E)  small intestine (pH 8) 
A)  stomach (pH 2) 
B)  liver (pH 5) 
C)  pancreas (pH 7) 
D)  blood (pH 7.4) 
E)  small intestine (pH 8)

Question 2

According to the following graph of activity as a function of pH, at which of the following pH values 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 3

Which statement 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 4

The structure of one of the first ACE inhibitors is given below.What is the purpose of the sulfur in this molecule?

Accepted Answer

A)  It is highly reactive with angiotensin II. 
B)  It binds to a metal on the exterior of ACE. 
C)  It holds the molecule in the active site of ACE. 
D)  It makes Captopril into a strong acid. 
E)  It forms a covalent bond with ACE, permanently deactivating it. 
A)  It is highly reactive with angiotensin II. 
B)  It binds to a metal on the exterior of ACE. 
C)  It holds the molecule in the active site of ACE. 
D)  It makes Captopril into a strong acid. 
E)  It forms a covalent bond with ACE, permanently deactivating it.

Question 5

The amino acid sequence is the ________ of a protein.

Accepted Answer

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

Question 6

The following is a description of an enzyme called superoxide dismutase.Refer to this paragraph to answer the following question. Superoxide dismutase is an enzyme that detoxifies a free radical called superoxide.This radical is responsible for causing injury during reperfusion after a heart attack, and is also thought to play a role in Parkinson's Disease.a Depending on what organism the protein is found in, it occurs either as a dimer or tetramer of identical subunits.b The subunits are mostly α-helical with some β-sheet near the C-terminus.c A metal binding site for manganese, iron, nickel or copper/zinc is composed of residues from both the N-terminus and the C-terminus.d These residues are: His-26, His-81, Asp-167, His-171.e
Which statement refers to a prosthetic group?

Accepted Answer

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

Question 7

Which statement BEST describes the purpose of a catalyst in a chemical reaction?

Accepted Answer

A)  to speed up the rate of the reaction 
B)  to lower the energy of the reactants 
C)  to slow down the rate of the reaction 
D)  to lower the energy of the products 
E)  to increase the activation energy of the reaction 
A)  to speed up the rate of the reaction 
B)  to lower the energy of the reactants 
C)  to slow down the rate of the reaction 
D)  to lower the energy of the products 
E)  to increase the activation energy of the reaction

Question 8

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

Question 9

Which of the following amino acids contain a thiol?

Accepted Answer

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

Question 10

Which of the following correctly shows the electrostatic interaction between amino acids that holds an α-helix or β-pleated sheet together?

Accepted Answer

A)  -CH2S-SCH2- 
B)    
C)    
D)    
E)  Any of these can act as the electrostatic interaction. 
A)  -CH2S-SCH2- 
B)    
C)    
D)    
E)  Any of these can act as the electrostatic interaction.

Question 11

What is the relationship between the following two molecules?

Accepted Answer

A)  They are enantiomers. 
B)  They are identical. 
C)  They are conformers. 
D)  They are constitutional isomers. 
E)  They are unrelated. 
A)  They are enantiomers. 
B)  They are identical. 
C)  They are conformers. 
D)  They are constitutional isomers. 
E)  They are unrelated.

Question 12

Which of the following are methods of denaturing a protein?

Accepted Answer

A)  pH changes 
B)  heating 
C)  mechanical agitation 
D)  detergents 
E)  All of the above are methods. 
A)  pH changes 
B)  heating 
C)  mechanical agitation 
D)  detergents 
E)  All of the above are methods.

Question 13

The C-N bond that joins amino acids together to form a peptide is called a(n)_________ or a(n)__________ bond.

Accepted Answer

A)  amide; peptide 
B)  carbonyl; amine 
C)  protein; amine 
D)  peptide; carbonyl 
E)  amine; peptide 
A)  amide; peptide 
B)  carbonyl; amine 
C)  protein; amine 
D)  peptide; carbonyl 
E)  amine; peptide

Question 14

Which of the following amino acids can form a disulfide bridge?

Accepted Answer

A)  serine 
B)  alanine 
C)  cysteine 
D)  aspartic acid 
E)  lysine 
A)  serine 
B)  alanine 
C)  cysteine 
D)  aspartic acid 
E)  lysine

Question 15

What type of bond is a peptide bond?

Accepted Answer

A)  an ionic bond 
B)  a nonpolar covalent bond 
C)  a polar covalent bond 
D)  a hydrogen bond 
E)  a salt bridge 
A)  an ionic bond 
B)  a nonpolar covalent bond 
C)  a polar covalent bond 
D)  a hydrogen bond 
E)  a salt bridge

Question 16

What is the relationship between the following two molecules?

Accepted Answer

A)  They are enantiomers. 
B)  They are identical. 
C)  They are conformers. 
D)  They are constitutional isomers. 
E)  They are unrelated. 
A)  They are enantiomers. 
B)  They are identical. 
C)  They are conformers. 
D)  They are constitutional isomers. 
E)  They are unrelated.

Question 17

What is indicated by the arrow pointing to part of the Fischer projection below?

Accepted Answer

A)  the beta carbon 
B)  the anomeric carbon 
C)  a chirality center 
D)  a secondary amine 
E)  a peptide bond 
A)  the beta carbon 
B)  the anomeric carbon 
C)  a chirality center 
D)  a secondary amine 
E)  a peptide bond

Question 18

How is the following amino acid classified?

Accepted Answer

A)  nonpolar 
B)  polar neutral 
C)  polar acidic 
D)  polar basic 
E)  None of the above is a correct classification. 
A)  nonpolar 
B)  polar neutral 
C)  polar acidic 
D)  polar basic 
E)  None of the above is a correct classification.

Question 19

When several amino acids are connected together, head-to-tail, the resulting molecule is called a(n)__________.When more than 50 amino acids are connected together, the molecule is called a(n)___________.

Accepted Answer

A)  enzyme; polypeptide 
B)  protein; polypeptide 
C)  polypeptide; protein 
D)  polypeptide; enzyme 
E)  nucleic acid; enzyme 
A)  enzyme; polypeptide 
B)  protein; polypeptide 
C)  polypeptide; protein 
D)  polypeptide; enzyme 
E)  nucleic acid; enzyme

Question 20

The purpose of an enzyme is to

Accepted Answer

A)  be structural in nature. 
B)  transport key molecules. 
C)  defend the body against infectious agents. 
D)  catalyze chemical reactions. 
E)  All of these are purposes of enzymes. 
A)  be structural in nature. 
B)  transport key molecules. 
C)  defend the body against infectious agents. 
D)  catalyze chemical reactions. 
E)  All of these are purposes of enzymes.

Below is a graph of enzyme activity as a function of pH.Given the information on this graph, where is pepsin most likely to be found?

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

Which statement about enzyme names is FALSE?

The structure of one of the first ACE inhibitors is given below.What is the purpose of the sulfur in this molecule?

The amino acid sequence is the ________ of a protein.

Which statement BEST describes the purpose of a catalyst in a chemical reaction?

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

Which of the following amino acids contain a thiol?

Which of the following correctly shows the electrostatic interaction between amino acids that holds an α-helix or β-pleated sheet together?

What is the relationship between the following two molecules?

Which of the following are methods of denaturing a protein?

The C-N bond that joins amino acids together to form a peptide is called a(n)_ or a(n)__ bond.

Which of the following amino acids can form a disulfide bridge?

What type of bond is a peptide bond?

What is the relationship between the following two molecules?

What is indicated by the arrow pointing to part of the Fischer projection below?

How is the following amino acid classified?

When several amino acids are connected together, head-to-tail, the resulting molecule is called a(n).When more than 50 amino acids are connected together, the molecule is called a(n)_.

The purpose of an enzyme is to

Matter, Energy, and Measurement

Atomic Structure and Radioisotopes

Ionic and Covalent Compounds

Molecular Geometry, Polarity, and Intermolecular

Chemical Quantities and Introduction to Reactions

Chemical Reactions: Energy, Rates, and Equilibrium

Changes of State and Gas Laws

Mixtures, Solution Concentrations, and Diffusion

Acids and Bases, Ph, and Buffers

Introduction to Organic Chemistry:

Alcohols, Phenols, Thiols, Ethers, and Amines

The Carbonyl Containing Functional Groups

The Common Organic Reactions in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

Filters

Exam 16: Proteins: Structure and Function

Below is a graph of enzyme activity as a function of pH.Given the information on this graph, where is pepsin most likely to be found?

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

Which statement about enzyme names is FALSE?

The structure of one of the first ACE inhibitors is given below.What is the purpose of the sulfur in this molecule?

The amino acid sequence is the ________ of a protein.

Which statement BEST describes the purpose of a catalyst in a chemical reaction?

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

Which of the following amino acids contain a thiol?

Which of the following correctly shows the electrostatic interaction between amino acids that holds an α-helix or β-pleated sheet together?

What is the relationship between the following two molecules?

Which of the following are methods of denaturing a protein?

The C-N bond that joins amino acids together to form a peptide is called a(n)_________ or a(n)__________ bond.

Which of the following amino acids can form a disulfide bridge?

What type of bond is a peptide bond?

What is the relationship between the following two molecules?

What is indicated by the arrow pointing to part of the Fischer projection below?

How is the following amino acid classified?

When several amino acids are connected together, head-to-tail, the resulting molecule is called a(n)__________.When more than 50 amino acids are connected together, the molecule is called a(n)___________.

The purpose of an enzyme is to

Matter, Energy, and Measurement

Atomic Structure and Radioisotopes

Ionic and Covalent Compounds

Molecular Geometry, Polarity, and Intermolecular

Chemical Quantities and Introduction to Reactions

Chemical Reactions: Energy, Rates, and Equilibrium

Changes of State and Gas Laws

Mixtures, Solution Concentrations, and Diffusion

Acids and Bases, Ph, and Buffers

Introduction to Organic Chemistry:

Alcohols, Phenols, Thiols, Ethers, and Amines

The Carbonyl Containing Functional Groups

The Common Organic Reactions in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

Filters

The C-N bond that joins amino acids together to form a peptide is called a(n)_ or a(n)__ bond.

When several amino acids are connected together, head-to-tail, the resulting molecule is called a(n).When more than 50 amino acids are connected together, the molecule is called a(n)_.