Preparation of Slides

Before any specimen can be examined under a microscope, it has to be mounted onto a slide, and the exact mounting method depends on what part of the specimen actually needs to be seen. A whole mount is the simplest approach - an entire small organism, or a smaller structure taken from a larger one, is placed directly onto a slide and observed as a complete unit. A squash preparation is used when the material needs to be crushed or squashed flat on the slide in order to properly reveal its internal contents; pollen grains, and root-tip or flower-bud tissue prepared to observe the chromosomes during mitosis or meiosis, are given as the standard examples of this technique. A smear is used for material that is already fluid, such as blood or a microbial culture, which is scraped, brushed or aspirated directly from the surface of an organ onto the slide; epithelial cells are the given example. Finally, a section is prepared by cutting thin free-hand or machine-cut …