system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is an optically inactive amino acid?
assistant
The correct answer is  Optical properties: All the amino acids except glycine possess optical isomers due to the presence of asymmetric carbon atom.
Ref: Satyanarayan 3rd edition page no: 49