Compare the effects of urea and beta mercaptoethanol on protein structure.

• A. Urea disrupts non-covalent interactions; beta mercaptoethanol cleaves covalent disulfide bonds
• B. Both disrupt non-covalent interactions
• C. Urea cleaves covalent disulfide bonds; beta mercaptoethanol disrupts non-covalent interactions
• D. Both cleave covalent disulfide bonds

Answer: (A)