Answer: Vitamin K.
- A Vitamin K
- B Vitamin C
- C Vitamin B12
- D Vitamin E
Correct answer: A. Vitamin K
Explanation: Vitamin K is essential for the synthesis of clotting factors (e.g., prothrombin).
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.