DNA Code - What is DNA?
The known life forms on planet Earth show a large degree of variation amongst each other. Yet all these varieties of life forms share one common basic construction material. All life forms are either made of cells or are a cell themselves, and all these cells have a nucleus. In this nucleus we find chromosomes, which in turn are made of DNA.
Viruses, by the way, are outside this definition. Viruses consist of genetic material with a shell of protein, but they are not made of one or more cells. It is not even clear yet whether viruses should be considered living creatures.
DNA or Deoxyribonucleic Acid is the carrier of the genetic instructions and of the instructions needed to guide the processes within the cells. DNA is composed of two very long chains of proteins, connected in pairs in a double spiral. Such a spiral can be compared to a zipper: each protein part has its own partner in the opposite chain. The zipper is used during the reproduction process: both the male and the female reproduction cells contain only one half of the DNA chains. At the moment of conception, the male and the female materials are "zipped" together to form a new chain, thus combining the genetic material of both parents. At this point, a new cell is created (a zygote) which now begins to replicate. A new life is developing.
For many years scientists have been working to map the human genome. The quest is focusing on the meaning of the code within the DNA. Every now and then cheers rise up from within the scientific community because a new milestone has been reached. Still there is much more mystery than clarity, and for good reason. We are researching a "language" we do not know and cannot learn this way. All we might achieve is the deciphering of parts of the code in a primitive way.
DNA Code - Computer Language and Memory
In computer languages, certain commands exist with which values in an existing or running computer system can be changed. In older computer systems, for example, the commands Peek and Poke were used: Peek would allow the programmer to "look at" a certain location, while Poke allowed him or her to change something in that location (the word "Poke" here is similar to the use of the word when the embers in a fireplace are poked; the contents are stirred). The syntax for these commands was: Peek “somewhere” and Poke “somewhere; value.”
Even in the early days of the home computer (in the early 80s), the thought of having 65,000 of such locations (or "addresses") available for manipulation was exciting and fascinating. Some addresses defined the color of the screen, while others produced a beep. Assigning a "bad value" to some locations would cause the computer to freeze. Pretty soon it became clear that it was not easy to be productive without a good "directory" of the available addresses: the user guide for the computer. The manufacturer of the computer created the address list and knew where each function resided.
In a general sense, a comparison can be drawn between DNA and the computer memory. Functions are stored in DNA similar to the way functions are stored in computer memory. Both DNA and computer memory have “home addresses” for each function. In many respects such an analogy is deficient, for example because DNA plays a role in the production of cells and because DNA, for "real-time" processing, first has to create copies of certain parts of a chain (RNA) which then are used for the real-time processing itself. Another example is the limited number of addresses (65.000) of the computer in the example, compared to the 220.000.000 gene pairs in the first chromosome of the human DNA alone! That means 3300 times as many addresses! And of course those gene pairs are far more complex and diverse than a memory address in a computer; altogether the base pairs in the human genome contain more than 23 billion DNA base pairs!
DNA Code - Evolution and gradual changes
The theory of evolution states that life forms have changed and improved gradually. These changes must take place in the genetic code, for an improvement of the species must be passed on to the descendants, and must be reproducible to be kept in future generations. In fact, changes in the DNA can only occur through so-called “mutations.” It is definitely not true that physical changes in a “realized body” could flow back into the genetic instruction set. If an animal would accidentally have its tail chopped off, and if this proved to be an advantageous change, this wouldn't mean that some generations later this change would somehow pop up in the genetic material.
What is a mutation? Occasionally errors occur in the DNA chain during the process of copying and reproducing. Suppose somewhere in the chain there is a sequence “DAABE” but after a reproduction, due to such an error, the copy reads “BEEBE.” Such a change could cause a change in the genetic properties of the genetic material.
Properties changed by mutations could theoretically be the basis of an improvement. But how could such an improvement of the design take place? For the sake of clarification, let's return to the example of the computer language. When a programmer writes a piece of software, the written code is made suitable for the computer memory through some processing of this code. Looking at the contents of such a program, it is clear it wouldn't be easy to make "blind" adjustments to the program and actually improve its function. Programmers know that it might be possible to make simple cosmetic changes by using extreme caution, but they are also well aware that it would be impossible to actually add functionality to the program in this manner.
Imagine a computer program is written to perform simple calculations: additions and subtractions. How likely would it be that such a program could be modified, by applying blind or random changes, to enhance its functionality to include divisions or even square roots? Or would it be possible for random mutations to create new functionalities?