Histology is the microscopic counterpart of gross anatomy. It focuses on larger structures that are not visible under a microscope. The condition of an organ, tissue, or body fluid produced by a disease. Pathology is the study of the causes and effects of disease or injury. Most fresh tissue specimens are colorless and soft. They provide little useful information. For scientific or diagnostic purposes, tissue specimens must undergo substantial changes in preparation for microscopic observation.
Standards organization preparation has four steps.
- Fixation: it can stabilize and protect the organization.
- Embedding: the transformation of tissue into a solid form that can be sliced ("sliced").
- Section: provide very thin specimens for microscopic examination.
- Staining: provides visual contrast and facilitates the identification of specific tissue components.
Tissue Embedding and Sectioning
After fixation, tissue specimens are usually embedded in solid materials to support very thin sections.
In order to embed tissue samples, tissue water is first replaced by solvents such as alcohol and xylene, and then by liquids such as molten wax (Paraffin) or epoxy resin solution, which can then be cured by cooling or polymerization.
Slices are very thin slices produced from tissue samples. Slicers can be as simple as razor blades, or they can be complex machines that cost tens of thousands of dollars.
Accessories for Sterilisation
Tools for Tissue and Histology Preparation
Special Instruments for Tissue Pruning
Tissue, Cassettes, and Base Molds for Tissue Embedding
Staining
Most cells are basically transparent, with little or no internal pigment. Even hemoglobin rich red blood cells are almost colorless when they are not stained, unless they are squeezed into thick blocks. The dye is used to give contrast and make the tissue components obvious. Some special dyes that selectively bind specific components can also be used to identify these structures. But the basic function of dyeing is to make the structure easier to see.
Slides and Coverglasses for Microscopy Observation
Slides Staining, Storage and Shipping
