Acidic amino acids are: (A) Asparagine, (B) Arginine, (C) Glutamine, (D) None
Answer is D. aspaic acid and glutamic acid are proton donors. At physiologic pH, the side chains of these amino acids are fully ionized, containing a negatively charged carboxylate group (-COO-). They are, therefore, called aspaate or glutamate to emphasize that these amino acids are negatively charged at physiologic pH Asparagine and Glutamine are neutral amino acids. Ref: LIPPINCOTT's Biochemistry 6th Edition Pg No. 5.