AP BIOLOGY

Detailed explanation-1: -The phosphate backbone of DNA is negatively charged, which is due to the presence of bonds created between the phosphorus and oxygen atoms. In DNA structure, a phosphate group comprises one negatively charged oxygen atom, which is responsible for the entire strand of DNA to be negatively charged.

Detailed explanation-2: -The phosphate backbone of DNA is negatively charged due to the bonds created between the phosphorous atoms and the oxygen atoms. Each phosphate group contains one negatively charged oxygen atom, therefore the entire strand of DNA is negatively charged due to repeated phosphate groups.

Detailed explanation-3: -In double-stranded DNA, the molecular double-helix shape is formed by two linear sugar-phosphate backbones that run opposite each other and twist together in a helical shape. The sugar-phosphate backbone is negatively charged and hydrophilic, which allows the DNA backbone to form bonds with water.

Detailed explanation-4: -A nucleoside is essentially a nucleotide minus the phosphate group. A nucleotide has a nitrogenous base, a pentose sugar (ribose or 2′-deoxyribose), and one or more phosphate groups, while a nucleoside consists of the nitrogenous base and pentose sugar.

Detailed explanation-5: -Why does DNA have a negative charge? It happens because the nucleotides contain phosphate groups. The bonds created between oxygen and phosphorus atoms are negative, which makes the phosphate backbone negative. In the complete DNA structure, the phosphate group contains only one oxygen atom that is negative.