The branch of the U.S. government that is composed of the president and all the individuals, agencies, and departments that report to the president, and that is responsible for administering and enforcing the laws that Congress passes.
Proteins are biological polymers composed of amino acids. Amino acids, linked together by peptide bonds, form a polypeptide chain. One or more polypeptide chains twisted into a 3-D shape form a protein. Proteins have complex shapes that include various folds, loops, and curves.
Proteins are long molecular chains made from one of the 20 basic building blocks of life, Amino acids. The amino acids in a polymer are connected together by the peptide bonds between the carboxyl and amino groups of adjacent amino acids. The carboxyl group contains 1 carbon and 1 hydrogen atom and 2 oxygen atoms (CO-OH). The amine group contains 1 nitrogen atom attached to 2 hydrogen atoms (H-N-H).