Macromolecules Lipids, Carbohydrates, Nucleic Acid, Excerpt 2 MIT 7.01SC Fundamentals of Biology
Monomer of nucleic acids is called a nucleotide, which I will abbreviate NTIDE. And a nucleotide comprises three parts-- a phosphate, a sugar, and a base. Phosphate, sugar, base --that we will abbreviate P-S-B. The polymer of nucleotides makes up ribonucleic acid, RNA; or deoxyribonucleic acid, DNA. You need to know the full names of those. I'm not going to write them out. And those are all polynucleotides. And the way that polynucleotides are put together is through the joining of the phosphate and sugar into a sugar phosphate backbone, from which the bases hang. And so they look kind of like this. There's phosphate, sugar, phosphate, sugar, phosphate, sugar. And from the sugar hangs the base. The phosphate and the sugar, as I've just said, forms the sugar phosphate backbone. And the bases, as we'll discuss in a moment, comprise the information that is encoded in nucleic acids. Let's talk more about this nucleotide and the structure of the nucleotide ...