The Microscope

The Microscope

The invention of the microscope has opened up a world, perhaps more accurate, a universe smaller than we have yet to realize. It was crude in the beginning, a mere piece of round glass mounted in a metal plate capable of magnifying up to 275x. Antoni van Leeuwenhoek had no idea of the advancements to follow his invention in the 17th century.

Example of Leeuwenhoek's microscope



http://www.hps.cam.ac.uk/whipple/explore/microscopes/adutchpioneer/johnmayall/
Modifications to follow were multiple lenses, a light source and stage upon which to place specimens. Crude dials were improved to allow for fine focusing adjustments. Compound microscopes have the ability to magnify an object up to 2000x.
Picture of compound microscope
http://www.science.smith.edu/departments/Biology/Bio111/Labmanual/01CELLS.htm


To follow are images from the online lab simulating viewing through a compound microscope:

Onion Root Tip


The Letter "e"




Cheek Smear




Bacterial Capsule




A microscope works by placing an object on the stage which is illuminated from below. Adjustment knobs are utilized to position the object over the light source. Course and fine adjustments are then made to bring the object into focus which is viewed through the eyepiece.
The contribution that the microscope has made to science is significant. Amongst the optical microscopes, different types of light are utilized to better image certain tissues.
Electron microscopes generate magnetic fields in a vacuum which are then transmitted to a veiwing screen. This allows for much greater magnification, allowing us to see the fine details and structures inside organic cells.
Photo of electron microscope

http://www.astbury.leeds.ac.uk/facil/ElectronMicro/emsuite.htm

Some electron photos:

Staphylococci Bacteria


textbookofbacteriology.net/S.aureus.jpeg

Would you believe snowflakes?

http://www.nasa.gov/centers/goddard/news/topstory/2003/1223blacksoot.html


Credit: USDA Beltsville Agricultural Research Center in the Electron Microscopy Unit, Bld. 177-B, Beltsville Maryland 20705

Electron micrographs of frontal cortex neurons from control and PCP-treated organotypic cultures (rat brain slices). Panel A shows a normal neuron with intact cytoplasmic and nuclear membrane from a control culture. Panel B shows a very condensed nucleus of an apoptotic neuron from PCP-treated culture.

http://www.fda.gov/nctr/science/journals/text/vol5iss1/rrp0305.htm

As you can well imagine, the knowledge from observing these fine details has contributed much to the understanding of such small organisms and disease processes.