What is the term for the basic structure of protein?

The basic structure of protein is defined by amino acids. Proteins are composed of long chains of amino acids, which are organic compounds containing both an amine group and a carboxyl group. There are 20 different amino acids used in the synthesis of proteins, each of which has a unique side chain that determines its properties and contributes to the protein’s overall structure and function.

Amino acids link together through peptide bonds formed during a dehydration synthesis reaction, resulting in polypeptide chains that fold into specific three-dimensional shapes. These shapes are critical for the protein's functionality, making amino acids the fundamental building blocks of proteins.

Other options represent different biological macromolecules: nucleotides are the basic units of nucleic acids (like DNA and RNA), fatty acids are constituents of lipids, and simple sugars (monosaccharides) are the building blocks of carbohydrates. While these components are essential for various biological functions, they do not serve as the basic structure of proteins.