Carbohydrates are essential carbon-based molecules characterized by the presence of multiple hydroxyl groups, which consist of an oxygen atom bonded to a hydrogen atom. These compounds, also known as saccharides (derived from the Greek word for sugars), play a crucial role in biological systems. The term "carbohydrates" originated in the 1800s, referring to compounds with the general chemical formula CnH2On, indicating that carbon atoms are hydrated by water molecules.
Simple carbohydrates, or monosaccharides, adhere strictly to this formula. A prime example is glucose, the most abundant carbohydrate, which has the chemical formula C6H12O6. This formula reveals that glucose contains six carbon atoms, twelve hydrogen atoms, and six oxygen atoms, corresponding to six water molecules that hydrate the carbon atoms.
In contrast, complex carbohydrates may deviate from this formula and can include additional elements such as phosphorus, nitrogen, or sulfur. For instance, a complex carbohydrate might have the same number of carbon atoms as glucose but differ in the number of hydrogen and oxygen atoms, as well as include other atoms. This distinction is crucial for understanding the diversity of carbohydrate structures and their functions in biological systems.
As we delve deeper into the study of carbohydrates, the focus will primarily be on simple carbohydrates, while also acknowledging the existence and significance of complex carbohydrates. Understanding these foundational concepts will enhance your grasp of carbohydrate chemistry and its relevance in various biological contexts.