
Oct. 00
a.Lee
Name:_______________________________ Date:___________________ Period: _______
Microscope Worksheet
I. How Can a Microscope Help Us Study Living Things?
Microscope: an instrument that makes things look bigger
Biology: the study of living things.
Some living things are so small we can’t see them with the naked eye alone. Many of these are one
celled organisms called PROTOZOA [pro tuh ZO uh] and BACTERIA.
We can see such tiny things with the help of a high-power microscope. A microscope magnifies, or
makes things look bigger.
Have you ever used a magnifying glass? It is a simple microscope.
A magnifying glass, or hand lens, is easy to use. It doesn’t weigh much, and it’s easy to carry. But it
doesn’t magnify objects very much. We still cannot see one-celled plants and animals with a hand lens.
A compound microscope is much more powerful than a simple microscope. Most school microscopes
are compound microscope. They can make objects look 100 to 400 times as big as they really are. Some
compound microscopes magnify more than a thousand times. When we say “microscope,” we usually mean a
compound microscope.
The microscope has many uses, especially in biology – the study of living things.
Doctors often use microscopes. Is there one in your doctor’s office?
Parts of the Microscope
Eyepiece: Lens closes to the eye.
High Power Objective: Longer of the two lenses close to the slide.
Lower Power Objective: Shorter of the two lenses close to the slide.
Tube: Gives the distance needed between the eyepiece and objective.
Coarse Adjustment Knob: Moves the tube up and down.
Fine Adjustment Knob: Also moves the tube up and down but only slightly.
Base: Holds up the entire microscope.
Arm: Holds the tube and lenses. Connects to the base.
Nosepiece: Holds objective lenses.
Light: Shines light into the tube.
Diaphragm: Circular disk that lets more or less light pass through.
Stage: Platform for slide to rest. An opening in its center lets light pass through.
Clips(2): Hold the slide in place on the stage.
II. How Does a Microscope Magnify?
There are three lenses in the microscope. The
top lens is called the eyepiece. It is the lens closest to
the eye. The other two lenses are called objectives.
These are the lenses closest to the object. The object is
on a microscope slide. Different lenses magnify in
different powers. The power of magnification is marked
by a number with an x next to it. A lens that magnifies
ten times is marked 10x.
If the eyepiece is marked 10x and the objective 10x, then the total magnification is 100x. To find the total
magnification of a microscope, just multiply the two magnifications. Complete the table below by finding the
total magnification for each pair of lenses.