Topic overview

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Carbohydrates are polyhydroxy aldehydes or ketones, or substances that yield them on hydrolysis; their empirical formula often approximates (CH₂O)ₙ. They can be grouped by size, carbonyl type, or number of carbon atoms. Chiral centers give rise to stereoisomers, while cyclization forms pyranose or furanose rings. Derivatives and reducing properties provide further ways to distinguish carbohydrate types. Biologically, carbohydrates supply energy, store it as glycogen or starch, and contribute to structures such as cellulose and glycosaminoglycans. They also form parts of nucleic acids and cofactors, support cell recognition, and provide dietary fiber. These roles connect carbohydrate chemistry to cellular function and physiology.