KX Modifier - SPECIFIC REQUIRED DOCUMENTATION ON FILE. KX -- SPECIFIC REQUIRED DOCUMENTATION ON FILE. (EFFECTIVE DATE 7/1/2002) This modifier may be used to indicate that specific required documentation is on file in the patient's medical record. Documentation must be submitted upon request.
Proteins are made of amino acids hooked end-to-end like beads on a necklace. To simulate. a protein, you will make a model of your protein using a long chenille stem (the fuzzy. covered wire) and colored beads.
Proteins consist of one or more of these polypeptide chains. The primary structure of a protein is known as a polypeptide. From the two terminals of the polypeptide chain, N-terminus is where the amino group is free, and the c-terminus is where the carboxyl group is free. Polypeptides are synthesized at ribosomes.