Why learn about the four main classes of important biological macromolecules?

Fad diets: we’ve all heard about them and maybe followed one or two in our lives. These diets have strict rules, and often have restrictions on eating a certain thing like fats or carbs (carbohydrates).

There are several things to critically consider about this type of diet. First off, is it even possible for a person to cut all carbs out of their diet? More importantly, is it actually healthy to remove an entire class of molecules from the diet? Fats aren’t really important right? Certainly cholesterol is bad—right?

Before you decide to swear off carbs or fats, you should know that these types of foods are named after the kind of molecules that build them. Then you should learn what they actually do in cells.

Biological macromolecules are large molecules, necessary for life, that are built from smaller organic molecules. These large macromolecules are polymers, and their smaller building blocks are monomers. There are four major classes of biological macromolecules: carbohydrates, lipids, proteins, and nucleic acids (found in DNA and RNA). Each is an important component of the cell and performs a wide array of functions. Combined, these molecules make up the majority of a cell’s mass. Biological macromolecules are organic, meaning that they contain carbon. In addition, they may contain hydrogen, oxygen, nitrogen, phosphorus, sulfur, and additional minor elements. We’ll discuss each class and how they compare to each other.