By Dr. Maureen Hunter
The Molecules of life
You can learn a lot about yourself by talking turkey with a lube chemist.
Interviewer: So what’s your favorite thing about Thanksgiving?
Lube Chemist: That it’s mostly about eating. A diet rich in the molecules of life makes me think about my job of formulating oils.
Interviewer: How so?
Lube Chemist: Well, biology’s not so different from my field of lubrication engineering. Of course, the simplest life form is far more complex than the most advanced product of any human technology. But lubricants, like life, are based on carbon. Lubes are primarily based on hydrocarbons; that is, compounds of carbon and hydrogen. Life is primarily based on carbohydrates, compounds of carbon, hydrogen and oxygen.
Interviewer: So you’re saying life and lubes are made of the same stuff?
Lube Chemist: Yes, the same building blocks. Life’s molecules are formed from just a few elements. Carbon, hydrogen and oxygen comprise more than 98 percent of life’s atoms. Next comes nitrogen and then phosphorus and then sulfur. It’s very similar to lubricants.
Interviewer: So let’s get back to Thanksgiving. You said it was all about eating.
Lube Chemist: It sure is, and who doesn’t like a state-sanctioned gorging event where you can chow down as many as 4,500 calories in one sitting? As humans we have 100 trillion cells, and we need to energize those cells. Four types of molecules perform the majority of chemical operations in cells: carbohydrates, lipids, proteins and nucleic acids. Carbohydrates contain lots of energy and play a key role in the metabolism of cells. Lipids, which include oils, fats and waxes, are characterized by their insolubility in water, which makes them ideally suited to forming cell membranes. It actually makes me think of rust preventives and eating turkey.
Lube Chemist: And lubes in general. Lipids are made of hydrocarbons with a few oxygen atoms. These are energy-storage molecules. Many lube oils are alkanes, carbons saturated with hydrogen. Simple lipids are very similar to this. They’re called fatty acids and have a hydrocarbon backbone from 4-36 carbon atoms. But at one end, instead of having a CH3 group like a lube oil, you have a COOH group. The COOH group is attracted to water, while the CH3 group is repelled by water. It makes for an interesting bipolar molecule—not unlike some of my in-laws who will be sitting around the Thanksgiving table (laughs).
Interviewer: That sounds interesting.
Lube Chemist: Yes, well, getting back to fatty acids, they provide building blocks for energy-storing fat cells. Fats cells are like tiny fuel-storage tanks filled with lipids, which is basically hydrocarbon energy. The energy content of lipids is actually very similar to that of fossil fuels.
Interviewer: And all this reminds you of eating turkey?
Lube Chemist: Lipids include oils and fats, and they’re the building blocks of cell membranes. All cells, including turkey cells, have cell membranes. I like all Thanksgiving foods—all those delicious carbohydrates and the proteins, too. That’s what my second helping of turkey is for.
Interviewer: So what do you usually do after Thanksgiving dinner?
Lube Chemist: After dinner you need a good beer during the football game. Fermentation is always another way of getting energy. It’s another form of metabolism—the incomplete reaction of an acid to alcohol in the absence of oxygen.
Interviewer: Do you ever exercise after Thanksgiving dinner?
Lube Chemist: Are you kidding? It’d take running a couple of marathons to burn off those 4,500 calories. After stuffing myself like a champ, I may put on my stretchy pants, but activity will just exhaust the supply of oxygen in my muscle cells. They’ll go into fermentation mode, form lactic acid and cause aching muscles. Beer is the only fermentation I want after dinner.
Interviewer: Any last comments?
Lube Chemist: Metabolism is how the body gains energy and atoms. Think about the atoms you eat on Thanksgiving Day. Atoms are just reused and recycled. Some of those atoms were once part of dinosaurs, fossil fuels, oils, turkeys and now part of you. It’s the history of life, and I’m thankful!
Maureen Hunter is the technical service manager for King Industries, Inc. in Norwalk, Conn.
You can reach him at firstname.lastname@example.org.
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