Category Archives: Microbiology

Powers of Ten

The Molecular Expressions Web site at Florida State University has a really cool interactive java tutorial to help get across the concept of orders of magnitude in relation to the relative size of objects in our world and universe:

View the Milky Way at 10 million light years from the Earth. Then move through space towards the Earth in successive orders of magnitude until you reach a tall oak tree just outside the buildings of the National High Magnetic Field Laboratory in Tallahassee, Florida. After that, begin to move from the actual size of a leaf into a microscopic world that reveals leaf cell walls, the cell nucleus, chromatin, DNA and finally, into the subatomic universe of electrons and protons.

In addition, this site has a plethora of information on microscopy, including a microscopy primer, a miscroscopy museum, a photo gallery and even a list of web resources. You an even try virtual microscopy with interactive java tutorials. For example, you can use scanning electron microscopy to get an up close look at a jellyfish or a gecko’s foot under the microscope.

The 5-Second Rule

Do you remember the “5-second rule”? Any food item dropped on the floor is “safe” to eat as long as it doesn’t remain on the floor for longer than five seconds before being picked up.

But is this actually a good rule to live by? A high school senior recently carried out a scientific study to find out whether or not the “5-second rule” was a good measure of food safety. The work was done during a seven-week internship at the University of Illinois at Urbana-Champaign (check out the UIUC press release here).

What a great example of making science fun and accessible to everyone!

Meet the Microbes

In 2002, the American Society for Microbiology and the National Association for Biology Teachers (NABT) released a set of 17 hands-on activities “that correlate with and build on the themes and ideas presented in the PBS series, “Intimate Strangers: Unseen Life on Earth.” This set of activities can be downloaded free of charge from the MicrobeWorld Activities website or can be purchased by NABT members on-line.

Note: I have used some of these activities in workshops with teachers and would highly recommend them.