Category: December, 2008

Fructose Mounting Medium for Permanent Slides

Many mounting media for making permanent microscope slides include organic solvents and are less suitable for the use in classrooms, at home and with children. In this article I would like to show you how to make fructose syrup to be used as a safe mounting medium.

Parts of a Compound Microscope

Here is a quick overview of the most important parts of a compound microscope (biological microscope) and their function.

Enhancing Photomicrographs

There are a range of different possibilities: Enhancing contrast: Photo editing software (such as Adobe Photoshop or GIMP) contain functions that enhance the contrast of an image. Find the menu point “Auto Levels” or simply “Levels”. This tool will make the darkest part of the image black (even if it was not black before) and [...]

Observing Brownian Motion

Brownian motion is the random movement of particles. It is possible to observe this movement under the microscope.

Staining Yogurt Bacteria

School microscopes are often not equipped with phase contrast optics, which would be suitable for viewing bacteria. It is possible to see bacteria also in regular bright field, but the results are better if they are stained. Yogurt bacteria are safe for the use in schools.

Some Safety Issues

Here are some safety issues to consider when doing microscopy lab work. This is not a comprehensive list.

Oblique Illumination

Oblique illumination is a contrast enhancing technique which can be realized with the use of home-made filters (patch stops) placed into the filter holder of the microscope condenser.

Darkfield Microscopy

Darkfield microscopy is one of the simplest and cheapest contrast enhancing techniques. It works well for specimens that have a refractive index which is different from its surrounding medium, but which are difficult to see because they lack color. Dark field microscopy shows the specimen bright on a dark background.

Types of Light Microscopes

This article outlines some similarities and differences between compound and stereo microscopes. They have different, but sometimes overlapping, areas of application.

Observing Leaf Stomata

It is possible to observe the impression of leaf epidermis cells on white wood glue. The stomata and guard cells are easily visible. The regular shape of the stomata makes it an ideal specimen for practicing drawing.