Which of the following amino acid if added to an acidic solution will have buffer action on solution at the physiological ph? a. alanine b. glycine c. histidine

Protein buffers in blood include haemoglobin (150g/l) and plasma proteins (70g/l). Buffering is by the imidazole group of the histidine residues which has a pKa of about 6.8. This ...

Histidine is an important amino acid, because its side chain has a pKa near the physiological pH, so it can participate as a buffer of blood pH.