Histopathology is the study of manifestations of disease through microscopic examination of tissues of plants and animals. Histopathology concentrates on the basic changes that happen in cells, tissues and organs when presented to harmful jolts. Histopathologists look at bigger bits of tissue to help in the analysis and treatment of patients. It is performed by examining cells and tissues under a light microscope, which have been sectioned, stained and mounted on a microscope slide.