Question 1

How many naturally occurring amino acids are there?

Accepted Answer

A)  1 
B)  5 
C)  10 
D)  20 
E)  hundreds 
A)  1 
B)  5 
C)  10 
D)  20 
E)  hundreds

Question 2

According to the graph below, which of the following is TRUE?

Accepted Answer

A)  At high temperature, the activity of the enzyme decreases more sharply than it does at low temperature. 
B)  At low temperature, the activity of the enzyme decreases more sharply than it does at high temperature. 
C)  The maximum activity is at the lowest temperature. 
D)  The maximum activity is at the highest temperature. 
E)  The activity of the enzyme is the same at all temperatures. 
A)  At high temperature, the activity of the enzyme decreases more sharply than it does at low temperature. 
B)  At low temperature, the activity of the enzyme decreases more sharply than it does at high temperature. 
C)  The maximum activity is at the lowest temperature. 
D)  The maximum activity is at the highest temperature. 
E)  The activity of the enzyme is the same at all temperatures.

Question 3

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 
A)  nonpolar 
B)  polar neutral 
C)  polar acidic 
D)  polar basic 
E)  None of the above

Question 4

The carbon with a smiley face over it is a(n)

Accepted Answer

A)  beta carbon. 
B)  anomeric carbon. 
C)  center of chirality. 
D)  secondary amine. 
E)  peptide bond. 
A)  beta carbon. 
B)  anomeric carbon. 
C)  center of chirality. 
D)  secondary amine. 
E)  peptide bond.

Question 5

Assuming that the enzyme represented by the graph below is found in humans, what temperature is most likely to be the optimum temperature?

Accepted Answer

A)  0ºC 
B)  10ºC 
C)  37ºC 
D)  55ºC 
E)  100ºC 
A)  0ºC 
B)  10ºC 
C)  37ºC 
D)  55ºC 
E)  100ºC

Question 6

Which of the following statements best describes a prosthetic group?

Accepted Answer

A)  They are nonpeptide molecules or ions essential to a protein's structure. 
B)  They are short peptide chains attached to a larger protein. 
C)  They are nonfunctional components of a protein. 
D)  They are the active part of a protein. 
E)  They are the part of the protein that provides structure. 
A)  They are nonpeptide molecules or ions essential to a protein's structure. 
B)  They are short peptide chains attached to a larger protein. 
C)  They are nonfunctional components of a protein. 
D)  They are the active part of a protein. 
E)  They are the part of the protein that provides structure.

Question 7

Is Gly-Ala-His the same tripeptide as His-Ala-Gly?

Accepted Answer

A)  No, they are constitutional isomers. 
B)  No, they are stereoisomers. 
C)  Yes, they are conformers. 
D)  Yes, they are the same molecule, just flipped over. 
E)  Yes, the written order of amino acids does not make a difference in the peptide. 
A)  No, they are constitutional isomers. 
B)  No, they are stereoisomers. 
C)  Yes, they are conformers. 
D)  Yes, they are the same molecule, just flipped over. 
E)  Yes, the written order of amino acids does not make a difference in the peptide.

Question 8

Which of the following statements best describes the function of an enzyme in the body?

Accepted Answer

A)  An enzyme acts as a buffer. 
B)  An enzyme transports waste out of the blood. 
C)  An enzyme signals cellular events. 
D)  An enzyme catalyzes chemical reactions. 
E)  All of the above 
A)  An enzyme acts as a buffer. 
B)  An enzyme transports waste out of the blood. 
C)  An enzyme signals cellular events. 
D)  An enzyme catalyzes chemical reactions. 
E)  All of the above

Question 9

Which of the following statements about quaternary structure is TRUE?

Accepted Answer

A)  Quaternary structure is the position of subunits in the overall structure of a protein. 
B)  All proteins have quaternary structure. 
C)  Quaternary structure is unaffected by acids or heat. 
D)  Quaternary structure is determined by the same interaction that holds an α-helix together. 
E)  Quaternary structure is how prosthetic groups are held in a protein. 
A)  Quaternary structure is the position of subunits in the overall structure of a protein. 
B)  All proteins have quaternary structure. 
C)  Quaternary structure is unaffected by acids or heat. 
D)  Quaternary structure is determined by the same interaction that holds an α-helix together. 
E)  Quaternary structure is how prosthetic groups are held in a protein.

Question 10

According to the following graph, the activity of the enzyme decreases more sharply at high temperature than at low temperature. What are the reasons for this observation?   I. As temperature is increased, the substrate binding slowly becomes poorer. II. As temperature is decreased, the enzyme moves more slowly and so reacts more slowly.
III) At higher temperatures, the enzyme is denatured and stops working entirely.
IV) Temperature has no effect on enzyme activity.

Accepted Answer

A)  I only 
B)  IV only 
C)  I and III 
D)  II and III 
E)  All are correct. 
A)  I only 
B)  IV only 
C)  I and III 
D)  II and III 
E)  All are correct.

Question 11

What is the charge on lysine, a basic amino acid, at physiological pH?

Accepted Answer

A)  "+2" 
B)  "+1" 
C)  "0" 
D)  "F1F1F1S1F1F1F101" 
E)  "F1F1F1S1F1F1F102" 
A)  "+2" 
B)  "+1" 
C)  "0" 
D)  "F1F1F1S1F1F1F101" 
E)  "F1F1F1S1F1F1F102"

Question 12

Is the peptide shown below chiral?

Accepted Answer

A)  No, molecules with multiple centers of chirality are not chiral. 
B)  Yes, it has centers of chirality. 
C)  No, it has no centers of chirality. 
D)  Yes, it has no centers of chirality. 
E)  It is not possible to determine whether or not the peptide is chiral. 
A)  No, molecules with multiple centers of chirality are not chiral. 
B)  Yes, it has centers of chirality. 
C)  No, it has no centers of chirality. 
D)  Yes, it has no centers of chirality. 
E)  It is not possible to determine whether or not the peptide is chiral.

Question 13

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

Accepted Answer

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

Question 14

Hemoglobin contains iron. The iron is an example of a(n)

Accepted Answer

A)  cofactor. 
B)  heme. 
C)  enzyme. 
D)  coenzyme. 
E)  metal. 
A)  cofactor. 
B)  heme. 
C)  enzyme. 
D)  coenzyme. 
E)  metal.

Question 15

In some proteins, hydrogen bonding occurs between polar residues and the surrounding aqueous environment, forcing the polar residues to the exterior of the protein. What are the interactions between the polar residues and the aqueous environment called?

Accepted Answer

A)  hydrophilic interactions 
B)  salt bridges 
C)  nonpolar interactions 
D)  hydrophobic interactions 
E)  dispersion forces 
A)  hydrophilic interactions 
B)  salt bridges 
C)  nonpolar interactions 
D)  hydrophobic interactions 
E)  dispersion forces

Question 16

How does your body know which proteins to make and in what order to place the amino acids when the proteins are synthesized?

Accepted Answer

A)  The body does not make proteins; they are consumed in the diet. 
B)  There are special proteins in which this information is encoded. 
C)  Our DNA acts as a blueprint for proteins. 
D)  Our brain does this subconsciously. 
E)  The answer is not known to science. 
A)  The body does not make proteins; they are consumed in the diet. 
B)  There are special proteins in which this information is encoded. 
C)  Our DNA acts as a blueprint for proteins. 
D)  Our brain does this subconsciously. 
E)  The answer is not known to science.

Question 17

What kinds of interactions are NOT part of tertiary protein structure?

Accepted Answer

A)  hydrophobic interactions 
B)  peptide bonds 
C)  hydrophilic interactions 
D)  salt bridges 
E)  disulfide bonds 
A)  hydrophobic interactions 
B)  peptide bonds 
C)  hydrophilic interactions 
D)  salt bridges 
E)  disulfide bonds

Question 18

An example of this type of protein is shown below.

Accepted Answer

A)  keratin 
B)  keratin, elastin, and collagen 
C)  membrane proteins and globular proteins 
D)  globular proteins 
E)  membrane proteins 
A)  keratin 
B)  keratin, elastin, and collagen 
C)  membrane proteins and globular proteins 
D)  globular proteins 
E)  membrane proteins

Question 19

About how many different proteins are in the human body?

Accepted Answer

A)  one hundred 
B)  one thousand 
C)  ten thousand 
D)  one hundred thousand 
E)  one million 
A)  one hundred 
B)  one thousand 
C)  ten thousand 
D)  one hundred thousand 
E)  one million

Question 20

At physiological pH, most carboxylic acids exist in their conjugate base form. Which of the following structures illustrates the conjugate base of a carboxylic acid?

Accepted Answer

A)  HCOOH 
B)  CH3COO+ 
C)  HCOO+ 
D)  HCOOF1F1F1S1F1F1F10 
E)  CH3COOH2+ 
A)  HCOOH 
B)  CH3COO+ 
C)  HCOO+ 
D)  HCOOF1F1F1S1F1F1F10 
E)  CH3COOH2+

How many naturally occurring amino acids are there?

According to the graph below, which of the following is TRUE?

How is the following amino acid classified?

The carbon with a smiley face over it is a(n)

Assuming that the enzyme represented by the graph below is found in humans, what temperature is most likely to be the optimum temperature?

Which of the following statements best describes a prosthetic group?

Is Gly-Ala-His the same tripeptide as His-Ala-Gly?

Which of the following statements best describes the function of an enzyme in the body?

Which of the following statements about quaternary structure is TRUE?

What is the charge on lysine, a basic amino acid, at physiological pH?

Is the peptide shown below chiral?

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

Hemoglobin contains iron. The iron is an example of a(n)

In some proteins, hydrogen bonding occurs between polar residues and the surrounding aqueous environment, forcing the polar residues to the exterior of the protein. What are the interactions between the polar residues and the aqueous environment called?

How does your body know which proteins to make and in what order to place the amino acids when the proteins are synthesized?

What kinds of interactions are NOT part of tertiary protein structure?

An example of this type of protein is shown below.

About how many different proteins are in the human body?

At physiological pH, most carboxylic acids exist in their conjugate base form. Which of the following structures illustrates the conjugate base of a carboxylic acid?

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

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Exam 13: Proteins: Structure and Function

How many naturally occurring amino acids are there?

According to the graph below, which of the following is TRUE?

How is the following amino acid classified?

The carbon with a smiley face over it is a(n)

Assuming that the enzyme represented by the graph below is found in humans, what temperature is most likely to be the optimum temperature?

Which of the following statements best describes a prosthetic group?

Is Gly-Ala-His the same tripeptide as His-Ala-Gly?

Which of the following statements best describes the function of an enzyme in the body?

Which of the following statements about quaternary structure is TRUE?

What is the charge on lysine, a basic amino acid, at physiological pH?

Is the peptide shown below chiral?

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

Hemoglobin contains iron. The iron is an example of a(n)

In some proteins, hydrogen bonding occurs between polar residues and the surrounding aqueous environment, forcing the polar residues to the exterior of the protein. What are the interactions between the polar residues and the aqueous environment called?

How does your body know which proteins to make and in what order to place the amino acids when the proteins are synthesized?

What kinds of interactions are NOT part of tertiary protein structure?

An example of this type of protein is shown below.

About how many different proteins are in the human body?

At physiological pH, most carboxylic acids exist in their conjugate base form. Which of the following structures illustrates the conjugate base of a carboxylic acid?

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