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 vary in structure as well as function. They are constructed from a set of 20 amino acids, which are linked to form polypeptide chains. Polypeptide chains that form distinct three-dimensional shapes constitute a protein. Below is a list of several types of proteins and their functions.