By electron microscopy, amyloid is seen to be composed of a "beta-pleated sheet" of fibrils, seen here as irregular grey material. When the amyloid protein is made up of immunoglobulin light chains, then it is "AL amyloid" and when it is derived from serum amyloid-associated protein, then it is "AA amyloid." In terms of the effect upon the organs, "amyloid is amyloid".