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Name: Karl
Status: Student
Age: 20s
Location: N/A
Country: N/A
Date: 2002

I have been curious about the atomic weight of DNA since reading Isaac Asimov's book on the Chemicals of Life and he mentioned how heavy a protein was in comparison to some inorganic compounds.

Hello again,

If I had known that Asimov's book was the root of your question, I would have mentioned that proteins are huge compared to inorganic molecules; as a matter of fact most organic molecules are much larger than most inorganic molecules. An amino acid consists of an amine group and an acid group with the amines fluctuating in size significantly, accounting for the different amino acids codons (only 64 possible combinations). DNA is just a library code to construct the different proteins in particular orders of operation. Asimov was unaware of the significance of operons and primers, so he did not gain a complete understand that DNA is really smaller than the massive accumulation of the proteins a DNA molecule can be coded to produce, and that RNA is really more the chief "creator" of living things (arguably) on the molecular level. DNA is principally a library that is "visited" when a code is needed. RNA does the work. DNA is the "master" molecule only in the sense of a library has the information needed. RNA reads the library and does all the work to make the functional proteins (this statement is simplified; actually there are a number (5+) of different RNAs working depending on the organism and the function). Yes, of course DNA is active and not interactive, I'm leaving that out!

You are going to have to forgive some of the omissions and simplifications above, for this topic is complex. I have assumed that you know some of the basic principles and can fill in the gaps.

Asimov was born too early, for if he was cognitively around today, I would think he would be dancing in the streets with how this all works (Human Genome Project, medical implications, etc.). Asimov, Bronowski, and many other mathematicians and physics did understand decades before the present that biology, and molecular biology in particular, will be the culmination of all that science has learned during the last 300 (Copernicus) or 2500 (Greeks) years (depending on your position of the History of Science). The "Century of Biology" has just begun.

Time magazine just recently offered the facts of how computer programming code is too big and a great deal can be learned from DNA code. Coding a human being is simpler than coding Word 2002! DNA coding is 8-9 times simpler in comparison.

What you are reading and the questions you asked, speaks volumes for you as an educator. It was fun thinking about all this.

Steve Sample
La Grange, Illinois

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