Final answer:
Each DNA nucleotide is comprised of a pentose sugar, a phosphate group, and a nitrogenous base. The sugar is deoxyribose in DNA, and there are four nitrogenous bases: adenine, guanine, cytosine, and thymine.
Step-by-step explanation:
Each DNA nucleotide is made up of three components: a pentose sugar, a phosphate group, and a nitrogenous base. The pentose sugar is deoxyribose in DNA. The four nitrogenous bases in DNA are adenine, thymine, cytosine, and guanine. Adenine and guanine are classified as purines, while cytosine and thymine are classified as pyrimidines. In contrast, RNA nucleotides contain the sugar ribose and replace thymine with uracil. Each nitrogenous base is attached to the sugar molecule, which is then attached to one or more phosphate groups, forming a nucleotide.