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.
When it is first produced by the cell, actin appears in a globular form (G-actin; see Figure 1). In microfilaments, however, which are also often referred to as actin filaments, long polymerized chains of the molecules are intertwined in a helix, creating a filamentous form of the protein (F-actin).