Answer: N-terminal amino acid.
- A C-terminal amino acid
- B Disulphide bridge position
- C N-terminal amino acid
- D Total number of residues
Correct answer: C. N-terminal amino acid
Explanation: Sanger reagent reacts with the free alpha-amino group at the N-terminus of a polypeptide, allowing identification of the N-terminal amino acid.
Two amino acids join via a condensation reaction: the carboxyl -OH of one and an amine -H of the other are eliminated as water, leaving a peptide bond (-CO-NH-) linking them into a dipeptide; repeating this builds a full protein chain.
Concept context
The chemistry of life: carbohydrates, proteins, lipids, nucleic acids, enzymes, and vitamins. Understand their structures, classification, and biological functions. Highly relevant for NEET and Class 12 board exams.