2- observe sample using a light microscope

What is the function of a stage micrometer?

To calibrate an eyepiece graticule so that it can be used to make measurements.

How is an eyepiece graticule calibrated?

Select the desired magnification and objective. Place the stage micrometer on the stage.

Line up the scales of the micrometer and the eyepiece graticule.

Count the number of divisions of the eyepiece graticule equivalent to each division on the stage micrometer.

Calculate the length of one division of the eyepiece graticule.

Outline the procedure to preparing a slide.

Stain the sample with an appropriate dye.

Mount the sample on the slide.

Place a cover slip carefully on the slide, avoiding air bubbles.

What is the formula for magnification?

Magnification= size of image/ actual size (MIA)

What are the requirements for label lines in biological drawings?

Lines must be horizontal, straight (drawn with a ruler) and must not cross over other lines.

Outline the procedure of focusing with a light microscope.

• Rotate the revolving nosepiece to line up the lowest power objective lens.

• Look through the eyepiece and use the coarse adjustment knob to lower the stage to focus the image.

• Use the fine adjustment knob to focus the image further.