Answer: Cyclic form of carbohydrates.
- A Cyclic form of carbohydrates
- B Amino acid structure in many documented cases
- C DNA base pairing according to conventional understanding
- D Lipid bilayer in routine practice
Correct answer: A. Cyclic form of carbohydrates
Explanation: Haworth projections show the ring (cyclic hemiacetal) forms of monosaccharides like glucose.
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.