Have
you ever wondered where the tissues you study come from?
Some are human tissues, and others are
from our more distant cousins. Human sources include surgical
specimens and tissue obtained at autopsy.
The methodologies and techniques used
in the preparation of tissues for study are extensive and beyond the
scope of this course. However, in order to interpret the images observed in
the light microscope, a basic understanding of light
microscopy tissue preparation and staining mechanisms is essential.
Tissue Preparation
1. Tissue removal and sampling.
2. Fixation (usually with an aldehyde solution). 3. Dehydration (replace water with alcohol).
4. Clearing (replace alcohol with solvent, e.g. xylene). 5. Embedding (paraffin or plastic).
6. Sectioning on microtome with steel or glass knives. 7. Staining (use of dyes and electron opaque stains).
Here are a few
things to think about. |