Proteins are a type of macromolecule composed of subunits called amino acids. They play essential roles in the body, such as catalyzing biochemical reactions and providing structural support. Unlike carbohydrates, lipids, and nucleic acids, proteins are uniquely defined by their amino acid composition. ;
Proteins are macromolecules made up of amino acid subunits, playing crucial roles in biological functions such as enzymatic activity and structural support. Unlike carbohydrates, lipids, and nucleic acids, proteins are uniquely defined by their amino acid composition. The correct answer to the question is option D. protein.
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