Protein Structure Quiz

If you were designing a molecule to be highly acidic, which functional group would you be sure to include in its sequence?

• hydroxyl

• amino

• carboxyl

• carbonyl

• none of the above

If you were going to be shown the structure of glycine, what functional group(s) would you expect to see?

• hydroxyl and amino

• amino and carbonyl

• carboxyl and amino

• carbonyl and hydroxyl

• carbonyl and sulfhydryl

A carbon skeleton is covalently bonded to both an amino group and a carboxyl group. When placed in water, it …

• A) will function only as an acid because of the carboxyl group.

• B) will function only as a base because of the amino group.

• C) will function as both an acid and a base.

• D) will function as neither an acid nor a base.

Which functional group can act as a base?

• amino

• phosphate

• hydroxyl

• carboxyl

• methyl

The biochemical reaction that joins two amino acids to form a dipeptide is accompanied by

• the addition of a water molecule

• the release of a carbon dioxide molecule

• the addition of a nitrogen atom

• the release of a water molecule

What structural feature makes the 20 common amino acids different from one another?

• different side chains (R groups) attached to the carboxyl carbon

• different side chains (R groups) attached to the amino groups

• different side chains (R groups) attached to an α carbon

• different asymmetric carbons

Which bonds maintain the primary structure of a protein?

• disulfide bonds

• hydrogen bonds

• ionic bonds

• peptide bonds

Which type of interaction stabilizes the α helix and the β pleated sheet structures of proteins?

• hydrophobic interactions

• ionic bonds

• hydrogen bonds

• peptide bonds

• covalent bonds

Bonds formed between the side chains (R groups) in a polypeptide are most important in stabilizing which of the following?

• primary structure

• secondary structure

• tertiary structure

• quaternary structure

Which of the following statements regarding the chemical reaction illustrated in Figure 3.11 is true?

• It is a hydrolysis reaction

• It results in a peptide bond

• It forms a disaccharide

• It forms two amino acids