Name the four main categories of biochemicals.

• A. Amino Acids, Nucleotides, Fatty Acids, Sugars
• B. Carbohydrates, Lipids, Proteins, Nucleic Acids
• C. Carbohydrates, Lipids, Proteins, Vitamins
• D. Carbohydrates, Proteins, Nucleic Acids, Minerals

Answer: (B)

The four main categories of biochemicals are the macromolecules that constitute the major functional building blocks of life: carbohydrates, lipids, proteins, and nucleic acids. Carbohydrates store and provide quick energy and also serve structural roles in cells (think of glucose for energy and starch or cellulose for structure). Lipids store energy more efficiently, form cellular membranes, and include fats, oils, phospholipids, and steroids that help with signaling and membrane structure. Proteins carry out the vast majority of cellular functions, acting as enzymes, transporters, receptors, and structural components, and they’re built from amino acids. Nucleic acids store genetic information and direct protein synthesis, with DNA as the long-term genetic material and RNA as the mediator that translates that information into proteins.

The other lists mix together monomer units or inorganic components rather than these four broad classes. Sugars, fatty acids, amino acids, and nucleotides are building blocks that assemble into the four main categories above, not the categories themselves. Vitamins and minerals are essential nutrients but aren’t one of the primary biomolecule classes.