Histopathology is the check of a biopsy or surgical sample which is performed by a pathologist, tracking down the sample that has been processed and histological units have been placed onto glass slides. If a big sample is assigned, like with the surgical method then a pathologist glimpses at the tissue specimen and chooses the portion which is most expected to produce a helpful and precise diagnosis - this portion is separated for analysis in a procedure usually learned as grossing or cut up. Bigger specimens are sliced to properly place their anatomical arrangements in the cassette. Particular specimens (particularly biopsies) can undergo agar pre-embedding to reassure accurate tissue exposure in the cassette and then in the block and then on the diagnostic microscopy glass slide. This is then set into a plastic cassette for the rest of the procedure.