Answer: Phosphodiester bond.
- A Phosphodiester bond
- B Glycosidic bond
- C Peptide bond
- D Hydrogen bond
Correct answer: A. Phosphodiester bond
Explanation: Nucleotides in a polynucleotide chain are linked by phosphodiester bonds (3'-5' linkage).
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.