Question 3 Some globular proteins are water soluble, while all fibrous/membrane proteins are water insoluble.
Which of the following statements BEST explains the reason for these differences?
A
Fibrous proteins have a large number of hydrogen bonds between the amino acids in the polypeptide chains that stabilize their structures, preventing solubility in water. The globular proteins that are water-soluble do not have as many hydrogen bonds between the amino acids in their peptide chains, allowing water solubility.
B
Fibrous proteins are configured in a way that exposes the polar side chains of the amino acids on the surface of the protein, preventing solubility in water. The globular proteins that are water soluble have nonpolar side chains on the surface of the protein, allowing water solubility.
C
Some globular proteins are configured in a way that exposes the polar groups of the amino acids on the surface of the protein, allowing water solubility. Fibrous proteins have nonpolar side chains on the surface of the protein, preventing water solubility.
D
Some globular proteins are composed of more than one polypeptide chain that weakly interacts with one another, allowing water solubility. Fibrous proteins are composed of only one polypeptide chain that tightly folds, preventing water solubility.