Identify the correct statements. A. Arginine and Tryptophan are essential amino acids. B. Histidine does not contain heterocyclic ring in its structure. C. Proline is a six membered cyclic ring amino acid. D. Glycine does not have chiral centre. E. Cysteine has characteristic feature of side chain as mathrmMeS-CH_2-CH_2-$\mathrm{MeS-CH_2-CH_2-}$. Choose the correct answer from the options given below:

### Core Logic A. Arginine and Tryptophan are indeed essential amino acids (cannot be synthesized by the human body). (Correct) B. Histidine contains an imidazole ring, which is a heterocyclic ring. So statement B is incorrect. C. Proline contains a pyrrolidine ring, which is a five-membered cyclic ring. So statement C is incorrect. D. Glycine is mathrmNH_2-CH_2-COOH$\mathrm{NH_2-CH_2-COOH}$. Because its alpha carbon has two identical hydrogen atoms attached, it lacks a chiral center. (Correct) E. Cysteine's side chain is a thiol group (-mathrmCH_2-SH$-\mathrm{CH_2-SH}$), not a thioether (mathrmMeS-CH_2-CH_2-$\mathrm{MeS-CH_2-CH_2-}$ which belongs to Methionine). So statement E is incorrect. Correct statements: A and D. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 12 Chemistry: Biomolecules