A snowflake is a marvelous thing when you look at it closely. They seem to be made perfectly from a random assortment of water droplets. How this chaos was turned into order was quite a mystery for hundreds of years. Now the mystery is solved and the solution was so simple that we might wonder what all of the fuss was about.
Water is formed from oxygen and hydrogen. The atoms in these molecules react according to laws of nature just as a magnet attracts in some cases, and repels in others. Electricity always flows from positive to negative according to known laws. Oil doesn’t mix with water and slippery things don’t stay together, all according to known laws of nature. Oxygen reacts with hydrogen differently depending on the temperature. For instance you may have read the directions for a certain paint or glue that tells you to not use it below 32 degrees. This is because the chemical reactions change and the paint might not stick to the wall or to itself at the lower temperature. If it freezes completely then it may be ruined because you have altered the arrangement of molecules and it just will never be the same.
Water isn’t quite that sensitive because, as we all know, we can freeze it and thaw it hundreds of times and it is still water. When it is frozen though, the atoms in oxygen react with the atoms in hydrogen according to known laws. Some particles are attracted to each other and some repel. The attractions are not strong at higher temperatures but at freezing temperatures they form into a hexagonal shape. If you look at this with the help of an electron microscope you will see the atoms themselves in a definite six sided order. They have no other choice anymore than we have a choice to be attracted to the earth by gravity. The forces of nature contained in atoms simply obey laws. They always do it and they cannot disregard the laws.
Like a honey comb, when water freezes it arranges itself into cell like structures with exactly six sides to each cell. There are endless ways that those six sided cells can arrange themselves together but the result will always be a basic hexagonal structure with perhaps various tails etc. branching off as they do into a snowflake. You will never see an octagonal or pentagonal snowflake. They have to follow the laws. Also I might add that it certainly cannot be said conclusively that no two flakes are ever alike. There is no reason why they cannot be but there is a definite law that says they must be built from a hexagon. Now if you can find some snow, put some on a cold plate and look at it with a magnifying glass. A snowflake is still a marvelous thing when you consider the laws behind it but it really is no miracle when inanimate particles obey those laws.
The same could be said for living things. After all, life has to obey laws as well. A certain chemical in your body reacts the same way as it does outside under the same conditions. The heating and cooling in a living thing causes chemicals to react the same way that they would out side of the body. In that sense the body or the living cell is no different than a snowflake. The miracle of life can generally be explained by known laws and chemical reactions. That is why scientists spend so much time with test tubes and flasks and various types of equipment that heats and cools or provides electrical currents or different rays of light and so forth. They know that the chemicals are going to do the same thing regardless of whether they are inside or outside the body. Why bother with all of the mess if you are only trying to discover how certain chemicals react with each other?
Life scientists spend a good deal of time injecting chemicals into various parts of the cell. Then they might deprive a certain chemical in a specific part of the cell. They may be trying to discover how a certain disease works so that they can formulate a chemical to counteract it. The laws are known so it is sometimes just a matter of finding the right chemicals under the right conditions.
DNA is formed by a series of chemical reactions. Unlike some chemicals that breakdown when life ceases or paint that breaks down when it freezes, DNA generally retains its shape and information. The famous Neanderthal man was examined along with the scraps of DNA that remained in long dead bone. DNA is not a living thing like a cell or an internal organ. It is like a chemical ladder that forms itself according to laws just like the snowflake does. Similarly for instance a rock forms according to law and lasts for thousands of years. In that sense DNA acts like a rock or a salt crystal. Of course when DNA is actually being used in a cell of an animal or plant it is doing far more than just sitting there like a rock or acting like a snow flake. But we will get to that part later.
Take an imaginary ladder and cut all of its rungs in half so that the ladder is in two long pieces with half rungs sticking out on each side. Set the ladder on the ground just like it would be before you cut it in half but leave a little space between the rungs that you just cut. Now start from one end of the ladder and write the letters, A, T, G, C on the rungs of one side of the ladder. Put the letters in any order that you want; repeats are allowed. For example the order you choose may look something like this: T G G C A C A A A C C T T T T T C C A G C T C A G G A A C T T C C A G G C
So now you have one half of the ladder marked and of course we want to mark the other half. Here is how you do it: Write these letters on the side that you haven’t marked yet according to the following instructions: Opposite of each T write an A. Opposite of each G write a C. Opposite of each C write a G and opposite of each A write a T. That is the basic structure of DNA except in real life the ladder is twisted into a spiral or "double helix" and is much longer. For instance it is several feet of microscopic ladder in a human. However long it is, you will almost always find the exact relationship of the letters. The letter A will always be opposite of T. The letter G will always be opposite of C. Of course in real life there are not actual letters but we have used them (and scientists use these exact letters) to represent specific chemicals. In nature these chemicals attract and repel each other according to established laws. That is why the T’s and A’s are always on the opposite sides of the same rungs of the DNA ladder. The order going up and down the ladder seems to be random but the opposite sides of each rung always follow the exact order mentioned. In 50 miles of DNA you will always find that A’s are opposite of T’s and G’s are opposite of C’s. It is simple chemistry just as predictable as a snowflake ordering itself into a hexagon.
Now what about the letters (or chemicals) that you initially arranged in any random order? In my instructions you remember that I said to put the 4 letters in whatever order that you wanted. This still is in some ways just simple chemical reactions. There is nothing miraculous about how they are put together if you think of four different people holding hands. They are joined together by their hands gripping each other. In that sense the 4 chemicals A, T, C, and G have no problem with holding hands with each other. They are not in the least bit prejudiced so they can be arranged in any order and they are still quite happy. The only question that remains really is what does the order mean to the living cell and the human being or plant that results from that seemingly random order of letters? Here is where simple chemical laws of nature break down. The reason they break down is not because chemical laws or the laws of physics are defied but because they cannot explain the order that, as it turns out, is not random at all. My analogy of the ladder was not correct in one place and that is where I told you to write the letters in any random order that you chose. In real life they appear to be random just like the ones that you did but they are in a precise order that represents a coded language.
I will even tell you what one of the codes means. But first let me give a brief explanation of RNA that is often used to copy parts of the information within DNA. The attractions of RNA are according to the same laws that work in DNA except the letter "U" replaces the letter "T" in the RNA code. Also RNA is only half a ladder. That is, it is like one half of the ladder that you made so that it can come between the halves of the DNA chain when it is opened and copy the portion of DNA that will be used in certain situations. There are other variations of RNA that we will explore some later. So the genetic code is certain combinations of the letters U,A,G and C. In this code the letters UAG mean stop. When certain chemical reactions are taking place in the cell, and they see that code (and a few other ones) they stop doing what they were doing. Other combinations of the coded letters give myriads of specific instructions for the making of various proteins and catalysts that are used in various ways including the translation and manipulation of the base code itself.
After the RNA has copied the information from the DNA it is used in various ways throughout the cell. You might say that the DNA is like a huge encyclopedia or dictionary that contains all of the information necessary to make and regulate a human being. If it is plant DNA then the information gives the specific instructions on how to make and maintain a specific plant or tree or whatever. The basic structure of DNA is the same in plants and animals and the code is the same as well. The DNA is really like a huge recipe book or dictionary with all the information that a person would need to make and maintain a person or a plant or whatever - assuming that we knew how exactly these basic instructions are interpreted and manipulated within the complex machinery of life.
Making life is possible, I suppose, if you can get permission from whoever wrote the instructions. Anyway let’s get back to our code and see if we can figure out a few things. The first question is, what caused this code to be arranged in such a precise order with no necessary chemical reactions compelling it? DNA is not just a random jumble of letters as it appears. It has been discovered that it is broken down into 3 letter codes (called codons) such as UAG, CCC, CUG, GCC, AAC, GCA, AGA, etc. Each three letter combination is like a word in a language. It is from these words that the instructions are written for the rest of the cell to follow in making a human being for example. That is how a baby is formed in the womb. It starts out with two cells following instructions and each time the cell divides those new cells follow their specific instructions. The DNA instructions are in each cell. They constantly reproduce themselves. These instructions are in your hair and in your skin and in your brain and in your liver. The whole encyclopedia and dictionary is in each cell. Millions of copies of precise instructions necessary to make a complete living human being are in your body. One copy is in each cell. When animals are cloned they only need the information from a single cell to do it because all of the information is there.
Each cell in the body knows which instructions to read from the DNA in order to perform its specific function. One cell may make more parts of a kidney according to precise instructions. Another cell may provide more energy according to the portion of the DNA recipe book that it is reading. Each cell reads and interprets the code and follows the instructions that it is given. Each cell knows which part of the instructions apply to it. Like a team of construction workers building a skyscraper, each worker reads the part of the plans that apply to his specific project. One worker may read the instructions on how to install windows, another may read the instructions on how to operate the elevator or crane, another may read the instructions on how to install the plumbing system and another follows instructions that pertain to the electrical wiring. In the end the entire building fits together perfectly according to the master set of instructions that are called DNA in a living organism.
After the building is built the DNA has only begun its continuing work of providing the base of information for maintaining, regulating, repairing and altering specific instructions according to continually changing factors. For instance, what to do when attacked by a foreign biological invasion which contains its own RNA (and destructive information) is provided for by the base instructions and information of DNA. Even the DNA in the most basic single celled organism contains more instructive DNA than is contained in our analogy of the construction workers reading blue prints and building codes etc.
It seems that now we have lost the ability to compare DNA to a snowflake. Now that we have entered the essence of DNA we find no comparison whatsoever. Chemical reactions and molecular or atomic structure are now nearly useless to us. The laws of nature now tell us nothing about the instructions in DNA. The simple natural explanations have now ended. Where now are the laws of physics? They have not been violated at all. They are simply irrelevant to this foundational portion of the life process upon which the rest of the operation of life rests.
Where did these minutely detailed precise instructions come from? How does each cell know what portion of the book to open to at any given time? It does no good for the glass maker to read about making an elevator. The crane operator needs to read about the weight loads he will be carrying but he couldn’t care less about how you make steel. The information in DNA, that is used in very specific ways and at the precise times necessary, cannot be explained by the laws of physics. We need another law before we can even hope to understand the origin of information like this. Snowflakes and interesting patterns and order in nature do nothing to help us here. Snowflakes and salt crystals do not give this type of instruction. Remember these instructions can be read, translated, understood and used to build a human being or a tree or a hummingbird or any animal or plant you can think of. There is even DNA in bacteria telling it how to do its good or evil and instructing it when to start and stop its job.