Ribose is classified as what type of biological molecule?

Ribose is classified as a carbohydrate because it is a simple sugar, specifically a pentose monosaccharide, composed of five carbon atoms. Carbohydrates are organic compounds made primarily of carbon, hydrogen, and oxygen, typically following the general formula Cn(H2O)n. Ribose fits this definition as it consists of a ring structure that includes these elements. As a key component of RNA (ribonucleic acid), ribose plays an important role in the structure and function of nucleic acids, but its classification as a carbohydrate is based on its molecular structure and composition.

Each of the other options represents a different type of biological molecule: proteins are made up of amino acids; lipids include fats and oils that are hydrophobic; and nucleic acids like DNA and RNA are polymers made of nucleotide monomers. While ribose is crucial for the formation of nucleic acids, it remains a carbohydrate in terms of its chemical identity.