LIFE SCIENCE

Detailed explanation-1: -DNA is made up of two strands of polynucleotide chain in which the two strands are attached with hydrogen bonds. One nucleotide is attached with other nulceotide by phosphodiester bond. Phosphodiester bond is formed between third carbon and fifth carbon of two successive nucleotides.

Detailed explanation-2: -The nucleotides are covalently linked together in a chain through the sugars and phosphates, which thus form a “backbone” of alternating sugar-phosphate-sugar-phosphate (see Figure 4-3).

Detailed explanation-3: -A phosphodiester bond occurs between nucleotides, monomers that build nucleic acid, to form the sugar-phosphate backbone. Phosphodiester bond formation occurs by the removal of a water molecule when 2 hydroxyl groups from 2 different sugars bond with a phosphate group, thus it is known as a condensation reaction.

Detailed explanation-4: -At each point of juncture within a polynucleotide, the 5’ end of one nucleotide attaches to the 3’ end of the adjacent nucleotide through a connection called a phosphodiester bond (Figure 3). It is this alternating sugar-phosphate arrangement that forms the “backbone” of a DNA molecule.