Question 1

Which characteristic of amino acids is most responsible for the diversity of protein structures and functions?

Accepted Answer

The variety of R-groups (side chains) attached to the central carbon

Question 2

Amino acids polymerize to form proteins through a condensation reaction. What is the chemical equation for this reaction?

Accepted Answer

$\mathrm{Amino\ acid_1} + \mathrm{Amino\ acid_2} \rightarrow \mathrm{Peptide\ bond} + \mathrm{H}_2\mathrm{O}$

Question 3

Which of the following best describes the secondary structure of a protein?

Accepted Answer

The formation of alpha-helices and beta-pleated sheets due to hydrogen bonding between backbone groups

Question 4

A mutation changes a single amino acid in the primary structure of hemoglobin, causing the molecules to stick together. Which level of protein structure is directly affected by this mutation?

Accepted Answer

Primary structure

Question 5

Which type of R-group interaction is responsible for the formation of disulfide bonds in proteins?

Accepted Answer

Covalent bonding

Question 6

If a protein is denatured, which of the following is most likely to occur?

Accepted Answer

The protein will lose its normal function

Question 7

Which of the following best explains why enzymes are effective catalysts?

Accepted Answer

They hold substrates in a precise orientation at the active site

Question 8

Which of the following is NOT a function performed by proteins in cells?

Accepted Answer

Storage of genetic information

Question 9

A protein consists of two identical polypeptide subunits. What is this structure called?

Accepted Answer

Homodimer

Question 10

Which property of amino acid side chains determines whether an amino acid is hydrophilic or hydrophobic?

Accepted Answer

The polarity and charge of the R-group

Question 11

Which of the following would most likely aid the polymerization of amino acids into peptides in the oceans of early prebiotic Earth?

Accepted Answer

The presence of mineral surfaces for the amino acids to adhere to

Question 12

Which equation best represents the formation of a peptide bond between two amino acids?

Accepted Answer

$\mathrm{R_1NH_2COOH} + \mathrm{R_2NH_2COOH} \rightarrow \mathrm{R_1NHCO-R_2} + \mathrm{H_2O}$

Question 13

Which of the following is a real-world example of a protein with quaternary structure?

Accepted Answer

Hemoglobin, which consists of four polypeptide subunits

Question 14

Which of the following statements about prions is correct?

Accepted Answer

Prions are infectious agents caused by misfolded proteins

Question 15

Which equation describes the ionization of the amino group in water?

Accepted Answer

$\mathrm{NH_2} + \mathrm{H^+} \rightarrow \mathrm{NH_3^+}$

Question 16

Which of the following is NOT a type of interaction that contributes to the tertiary structure of proteins?

Accepted Answer

Peptide bond formation

Question 17

A protein is found to be unable to fold properly in the presence of heat shock. Which cellular component is most likely malfunctioning?

Accepted Answer

Molecular chaperones

Question 18

Which of the following best describes the hierarchical nature of protein structure?

Accepted Answer

Primary structure determines secondary structure, which folds into tertiary structure, and quaternary structure arises from interactions between tertiary structures

Question 19

Which of the following is a plausible reason why proteins were unlikely to be the first self-replicating molecules during the origin of life?

Accepted Answer

Proteins do not carry information required for replication

Protein Structure and Function: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards