Answer
Carbohydrates, as confirmed by Emil Fischer's groundbreaking research, play a pivotal role in various biological processes, primarily serving as sources of energy and structural components. These biomolecules, composed of carbon, hydrogen, and oxygen, encompass a wide range of compounds, including simple sugars, complex carbohydrates like starch and cellulose, and modified sugars such as glycoproteins. Fischer's extensive investigations into their composition, structure, and properties laid the foundation for contemporary carbohydrate chemistry.