Semester Unit: Introductory Biology
Quadrimester Unit: Cells and The Microscope
Web quest: Comparison of Microscopes used in Biology
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument
is called microscopy. There are many types of microscope used in biology. To provide a comparison of the different types of microscopes, research the
internet (using only reliable sources) to complete the following table.
Compound Microscope
Dissection Microscope
Scanning Electron Microscope
A dissection microscope is light
illuminated. The image that
appears is three dimensional. It
is used for dissection to get a
better look at the larger
specimen. You cannot see
individual cells because it has a
low magnification.
SEM use electron illumination.
The image is seen in 3-D. It has
high magnification and high
resolution. The specimen is
coated in gold and the electrons
bounce off to give you and
exterior view of the specimen.
The pictures are in black and
white.
Transmission Electron
Microscope
Provide an image
and a brief
description of
each type of
microscope.
Compound microscopes are light
illuminated. The image seen with
this type of microscope is two
dimensional. This microscope is
the most commonly used. You can
view individual cells, even living
ones.
TEM is electron illuminated. This
gives a 2-D view. A TEM works
much like a slide projector. A
projector shines a beam of light
through (transmits) the slide, as the
light passes through it is affected by
the structures and objects on the
slide. These effects result in only
certain parts of the light beam being
transmitted through certain parts of
the slide. This transmitted beam is
then projected onto the viewing
screen, forming an enlarged image
of the slide. TEMs work the same
way except that they shine a beam
of electrons (like the light) through
the specimen (like the slide).
Whatever part is transmitted is
projected onto a phosphor screen
Semester Unit: Introductory Biology
Quadrimester Unit: Cells and The Microscope
When was this
microscope
invented and who
invented it?
What is the
approximate
cost?
What is the range
of magnification?
What is the
source of
Illumination?
What are the
specimens
mounted on?
Provide an
example of an
image seen
through this type
of microscope.
In the late 1590’s Hans Lippershey
and his son, Zaccharias Hanssen
were experimenting with a variety
of lenses in a tube and were
amazed to see that the object at
the end of the tube was magnified
significantly beyond the capability
of a magnifying glass.
Philip O. Gravelle, a chemist,
developed the dissecting
microscope in the 1920’s to
compare bullets for identification
in forensics.
Co-invented by Germans, Max
Knoll and Ernst Ruska in 1931,
Ernst Ruska was awarded half of
the Nobel Prize for Physics in
1986 for his invention.
for the user to see.
Co-invented by Germans, Max Knoll
and Ernst Ruska in 1931, Ernst
Ruska was awarded half of the
Nobel Prize for Physics in 1986 for
his invention.
$150 - $1500
$100-$1500
more than $50,000
more than $50,000
x40 – x400
(without oil immersion lens)
Up to x30
about x10 to x1,000,000
about x10 to x1,000,000
visible light
visible light
electrons
electrons
glass slides
Specimens are not mounted but
are generally viewed on a glass
petri dish.
Onion epidermis
Lepidoptera
Mounted on metal stubs (such as
aluminium) and then covered in
an ultrathin coating of conductive
material such as gold or
platinum..
A seed of a tobacco plant
Thin films of collodion or other
supporting material on copper grids.
C. elegans (nematode) egg