Protein is described as what type of organic compound?

Protein is classified as an organic compound primarily because it is composed of one or more chains of amino acids. Amino acids are the building blocks of proteins and contain both an amino group and a carboxyl group, along with a side chain that differentiates one amino acid from another. This unique structure allows proteins to perform a vast array of functions in the body, including catalyzing metabolic reactions, providing structural support, and facilitating communication between cells.

The reason behind this classification is that proteins contain carbon, hydrogen, oxygen, and nitrogen, which are characteristic elements of organic compounds. The arrangement of these amino acids into polypeptide chains further defines the properties and functions of specific proteins, as the sequence and type of amino acids will influence how the protein folds and what its role in the organism will be.

Other options do not correctly define proteins: fatty acids are components of lipids, inorganic compounds do not contain carbon-hydrogen bonds, and simple sugars refer to carbohydrates, which differ structurally and functionally from proteins.