You may be given some prepared slides of blood to examine with the microscope.
Many types of blood cell are 10 μm in size or less. You will need high power to examine them.
The slides will have been stained to show the cells, and cell features. The micrograph shows many red blood cells and three white blood cells.
An example of a commonly-used stain is Giemsa stain. It aids identification by staining:
|Red blood cells||Pink|
|White blood cell cytoplasm||Pale blue|
|White blood cell nuclei||Magenta|
To use a light microscope to see blood cells in a smear.
Rotate the objective lenses so that the low power, eg ×10, is in line with the stage.
Turn the coarse focus so that the stage is as close to the objective lens as possible.
You should not look through the microscope to do this.
Place the microscope slide on the stage.
Line it up so that the specimen – if you can see it – is in the centre of the stage, where the light passes through.
Focus the slide towards you by turning the coarse focus adjustment.
You are likely to see an image like this. Here you can see larger white blood cells and smaller red blood cells. The cells have been stained using Wright's solution stain.