Which of the following amino acids has the highest pKa value?
Arginine is obtained by applying the relevant formula or quantitative relationship to the given parameters. In Titration of Amino Acids, numerical problem-solving requires understanding the mathematical relationships between biological variables. The calculation involves substituting the provided values into the appropriate equation and solving systematically. The other options (Aspartic acid, Histidine, and Cysteine) result from common calculation errors such as using incorrect formulas, misidentifying variables, inverting ratios, or making arithmetic mistakes.
Ref: Lehninger Principles of Biochemistry, Nelson & Cox, 8th Ed., Ch. 3