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.
Protein Structure. 1  Proteins are macromolecules that play many functions in the cell. 2  They are used for support, storage, transport of other substances, defense against invaders, and catalytic enzymes. 3  This is just a brief overview of protein structure. Proteins are composed of repeating units called amino acids.