Polarized light scattered from small particles -- spheres, fibers, dust, defects and biomaterial -- carries information about the optical and geometrical properties and even more esoteric properties of the scatterer. This highly developed, powerful, but under used technique is sensitive enough to detect a 0.5 nanometer radius change in a 1.0 micron diameter quartz fiber. The complete set of 16 polarized light scattering signals from any scatterer form a 16- element Mueller matrix, Sij, which is the signature of the scatterer's status quo. Changes in cell morphology, internal arrangement and metabolic activity cause changes in radius, refractive index and absorption and therefore changes in the polarization signals Sij which act as the probe. We demonstrate how the Sij can type human red blood cells, do bacteria autopsies, distinguish between different types of white blood cells, bacteria, spores, and study cell life cycle and degradation as biomaterial undergoes biologically significant change.