having or showing a disposition to avoid exertion; slothful: an indolent person. 2. Pathology. causing little or no pain; inactive or relatively benign: an indolent ulcer that is not painful and is slow to heal.
DNA and RNA are composed of nucleotides that are linked to one another in a chain by chemical bonds, called ester bonds, between the sugar base of one nucleotide and the phosphate group of the adjacent nucleotide. The sugar is the 3' end, and the phosphate is the 5' end of each nucleiotide.
An appropriate nucleotide triphosphate forms a hydrogen bond with an exposed base on the DNA strand. As another nucleotide triphosphate arrives to form a hydrogen bond at the next base, a bond forms between the 3\' OH group of the first nucleotide and the 5\' phosphate group of the new nucleotide. During this process, two phosphate groups are removed.