Monday, September 20, 2010


I grew up with scientists for parents, and they encouraged me to be curious. Once, for a lark, my father took it upon himself to teach me about chromatography. Now, it’s not very often that a father does this. In fact, I would hazard a guess that no more than 5 persons living in the U.S. right now have ever undergone this bonding experience.

One day, my father brought home the following: a long glass tube, a stopper with a small glass tube in it, a wad of glass wool, a short rubber hose with Hoffman clamp, a biuret stand and clamp, sugar, mortar and pestle and a large bottle of ether—enough to knock out every life-form within a one mile radius.

We started by setting up the column. This involved first grinding a lot of sugar in a mortar and pestle to reduce particle size to 50 microns. We then assembled the glassware and suspended the sugar particles in ether, swirling it in an Erlenmeyer, then slowly and carefully pouring the sugar/ether mixture into the tube, taking care that the sugar settle slowly to create an even column. After we had filled the column with sugar, we dried spinach, ground it in the mortar, suspended it in ether, filtered out the cellular debris, and carefully introduced the green ether onto the column.

We carefully unscrewed the Hoffman clamp and allowed the ether to drip out while slowly introducing fresh ether at the top. The spinach solution separated into a rainbow of colors, including green (chlorophyll), orange (a carotenoid pigment), yellow (another carotenoid), and red (still another carotenoid.) We then disassembled the column and pushed the sugar out, collecting the pigmented sections and washing them with ether to obtain four different pigments.

Many years later, I found out that fall colors are caused by the oxidation of chlorophyll, revealing these other pigments. The carotenoids, which are less sensitive to oxygen than chlorophyll, are used in the chloroplasts of plant cells to trap photons efficiently, making leaves powerful solar collectors.

Every experience in life accumulates and adds meaning to one’s existence. I am very grateful to my father for teaching me these simple but deep scientific facts. He made science human. To those of you who have experienced science mostly as humiliation and pain, I would like you to know that, given the right teacher, almost any subject comes alive and adds meaning to our lives.

In Ninth Grade, I took Biology from a teacher whom I greatly admired. She was attractive and she had us do all sorts of fun experiments such as pithing frogs, smoking drums by burning benzene and measuring tetani in muscles.

We each had to do a science project for this class. Like any 15-year-old, I wasn’t particularly driven to select a good experiment. My mother decided to stimulate my imagination by proposing that I work with something I had a lot experience with: grass. This experiment involved germinating grass seeds, then measuring height as a function of fertilizer type. Simple enough. However, because she worked in the pathology lab at the hospital, she thought of a very clever extension to the project: to embed the grass in wax, then run it on a microtome and make slides. We used xylene to dissolve the wax. Then we tinted the slides and studied cell dimensions under the microscope.

Years later, I realized that this experiment demonstrated the difference between quality and quantity. The best tea, the best coffee, the best arugula come from plants that have struggled a little. Using lots of nitrates (as they do in Salinas valley, home of the nation’s lettuce) makes the cells grow big and full of water. This produce the perfect lettuce for a burger. It does not promote flavor, however. As Alexander Solzhenitsyn said, “True art is only produced through suffering.”

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