Which term describes basic units of DNA that include a sugar, a phosphate, and a nitrogenous base?

Which term describes basic units of DNA that include a sugar, a phosphate, and a nitrogenous base?

• A. Deoxyribonucleotides
• B. Nucleosides
• C. Nucleotides
• D. Bases

Answer: (B)

DNA is built from units called deoxyribonucleotides. Each deoxyribonucleotide contains three parts: a deoxyribose sugar, a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). The sugar and phosphate form the backbone of the DNA strand through phosphodiester bonds, while the sequence of bases stores genetic information. A nucleoside, by contrast, has only sugar plus base and lacks the phosphate. Bases are just the nitrogen-containing rings themselves. In DNA synthesis, the building blocks are the deoxyribonucleotide triphosphates, which supply energy and the phosphate groups needed to add onto the growing strand.

DNA is built from units called deoxyribonucleotides. Each deoxyribonucleotide contains three parts: a deoxyribose sugar, a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). The sugar and phosphate form the backbone of the DNA strand through phosphodiester bonds, while the sequence of bases stores genetic information. A nucleoside, by contrast, has only sugar plus base and lacks the phosphate. Bases are just the nitrogen-containing rings themselves. In DNA synthesis, the building blocks are the deoxyribonucleotide triphosphates, which supply energy and the phosphate groups needed to add onto the growing strand.