Engines of Our Ingenuity

No. 513:

by John H. Lienhard

Click here for audio of Episode 513.

Today, I learn about more than DNA. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

Robert Hazen and James Trefil are two scientists who've been studying scientific illiteracy. Hazen recently spoke to group of geophysicists. He asked them to distinguish between RNA and DNA. Only two out of 25 could.

I also came up short. I didn't know the difference, either. I knew the very nature of our being is vested in them; but how? Hazen exposed a huge scientific illiteracy in my own life.

He had my attention. Maybe those of us who work in science and technology are our own worst enemies. We often lay claim to ignorance of anything but our own area. It seems that by knowing heat transfer, I'd let myself be ignorant of biology.

So I put the question to a biochemist. He began by reciting the structure of the DNA molecule. My first reaction was to cut him off. I wasn't interested in organic chemistry. I only wanted the answer.

But then I relaxed and paid attention. A biochemist was sharing his knowledge on his terms. To understand, I had to meet him there. He was absolutely right. I had to hear him out. If I didn't come to terms with details, I would know nothing.

DNA is a wonderfully elegant molecule. It's also very stable. RNA is only slightly different. It's less stable. RNA presents the information from DNA in an interactive form. RNA puts the DNA code to work making protein for our cells. It shapes those cells for the brain or muscles, blood or skin.

DNA is the archival record of our being. It's carried in every cell of our body. RNA is the working copy of that record. DNA is like the American constitution buried in a Washington vault. RNA is like the working law. It's fractional and varied, but it always reflects that document in the vault.

From the biochemist, I went to a biophysicist. She told me about the human genome and the structure of genes and chromosomes. After just two hours spent patching my ignorance, I emerged far richer. I came away with renewed awe for the majesty of human life. I came away reminded that scientific knowledge is not a secret. But we ourselves often believe it is. We intimidate one another. I've known laymen far better equipped to speak across the lines we draw than we are.

Hazen and Trefil tell us we won't achieve scientific literacy when we wall ourselves off from each other. Scientific literacy means believing that we can understand what we don't know. We have to role-model that belief, that curiosity -- and that confidence -- before we ask it of the general public.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Pool, R., Science Literacy: The Enemy Is Us. Science, Vol. 251, 18 Jan., 1991, pp. 266-267.

I'm grateful to Dr. Mark Hadwiger and Dr. Janet Allen for their consultations on DNA and RNA. By the way, DNA stands for DeoxyriboNucleic Acid. RNA stands for RiboNucleic Acid. The prefix Deoxy means that a crucial hydroxyl group is missing in DNA. Hydrogen replaces it.


Model of a portion of the DNA molecule

The Engines of Our Ingenuity is Copyright © 1988-1997 by John H. Lienhard.
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