Biol 240H Course Blog
Posts will appear here for your own interest. They will not be covered on exams.
Saturday, January 17, 2026
Amazing images from microscopes
Friday, January 16, 2026
Breaking the resolution limit of light microscopy
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| image credit: HHMI |
"...that’s where we learned about photoactivatable fluorescent proteins.... it became obvious to Harald and me that this was the missing link for the idea that I had pitched after I left Bell: we could isolate a few molecules at a time by activating limited subsets of photoactivatable proteins. It seemed so easy."
"...We were both unemployed, but Harald had some of his equipment from Bell [Labs]..."
-from Betzig's Nobel speech
Xiaowei Zhuang's lab developed a similar method, called STORM, around the same time as PALM was developed. See "STORM image gallery" at her lab web site for some super-resolution images.
Thursday, January 15, 2026
Struggling with your grades? Fear not!
Watch the 45 seconds between 1:45 and 2:30 to see how Chemistry Nobel Laureate Marty Chalfie (of Green Fluorescent Protein fame) did in Chemistry classes in college.
Wednesday, January 14, 2026
Louis Pasteur and his home
Louis Pasteur's old house is now a museum, currently under renovation through 2028. You can see it well documented here. Pasteur is buried in the basement, in an elaborate crypt (pictured here).
Tuesday, January 13, 2026
Microns, nanometers, etc.
Powers of Ten, a classic Charles & Ray-Bernice Eames film on grasping the sizes of things from human scale out to the then-known universe, and back in to subatomic particles.
Friday, January 9, 2026
More images from Robert Hooke's Micrographia
Here's the whole book.
Hooke's book begins with an apology to the King of England, for, well, discovering things.
Hooke's methods for immobilizing some of the insects were creative:
...I gave it a Gill of Brandy, or Spirit of Wine, which after a while e'en knock'd him down dead drunk, so that he became moveless...
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| Hooke's engraving of a head of a hoverfly, from Micrographia |
Thursday, January 8, 2026
My favorite of van Leeuwenhoek's letters, with a surprise ending
In this letter, he describes finding microscopic life in frog poop. I especially like the surprise ending in the last 3 paragraphs – starting, "On the fifth day the Frog had dung'd again...." on the bottom of page 517. Scientific papers never end like this.
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| Google on van Leeuwenhoek's 384th birthday |
Wednesday, December 17, 2025
A popular book about cell biology
A great, vivid exploration of some fascinating topics in cell biology. See the "Read sample" button on the left side of this page to read parts of the book now. Also available as an audiobook.







