| abstract
| - One cannot talk about the mechanisms and functions and structure and chemistry of DNA without at some point thinking about how it all came to be in the first place. The whys and hows of it now were the whys and hows of it when it first came together. It is assumed at this time that evolution just had things "fall into place" over an almost umlimited time period. While it MAY have happened a long time ago, the assumption that it was basically an accident of chemistry and lightning and conditions is only in itself a speculation, though it is promulgated as fact to the lay public. DNA determines not only the gender and type of organisms, but also their morphology - their shape and size - and their proficiency at what they do. Small differences in the DNA code make huge differences in morphology. Yet, at the same time, huge differences in the size of organs within a human population, say, do not mean much at all in the FUNCTIONING of the overall organism. A book I read years ago - I had to send off to the University of Illinois for it long before the Internet began - was entitled something like "On the Morphology of Human Organs". It depicted the VERY wide range of human organ sizes. It was dealing with healthy, completely functional organs and not pathological ones. It was amazing the variations in size. (Size is only the grossest of measurements in deteriming anything about an organ.) In each organ typoe, the size difference was at least three-fold. For example, the hearts of perfectly healthy people were as big as a very large fist, while some were little bigger than large walnuts. Some aortas were the diameter oof a large thumb, while some were as narrow as a normal drinking straw. Yet, all these were funstioning perfectly well for their human hosts. And all had all the internal workings necessary. What in the DNA told one person's liver to be the size of a football, while some were like a small handbag? No matter the size, the relative internal operational areas were sufficient for full functionality. Since DNA tells each CELL what to be and where to be, and how to function and how long to live and how to interact with its neigbors, morphology is a silly thing to focus on, that is understood. DNA also tells each PART of the cell what to do, so that each cell is a mini-factory - that interfaces with the bloodstream, adjacent cells, and also with faraway endocrine glands and the brain. Cells have to communicate, and the DNA dictates not only the means of that commmunication, but the timing of it. It is now known that some of that communication entails protuberances on the outer surface of cells - at least in the bloodstream. That is how macrophages fight off disease microbes. These protuberances are designed to engage - by SHAPE - certain types of cells in the bloodstream. The question is this: HOW does the DNA tell the protuberances what shape to take? This author is a mechanical design engineer, and I can tell the reader that the shape of a part in a machine does not happen by chance. There is a saying that "Form follows function." What the part NEEDS to do dictates what its shape will be. The function also dictates certain other attributes, such as its material and how it needs to be hardened and coated before being put into use. While the main function of cells in an organism is thought to be chemical, there is some research that has been done that indicates that electrical qualities are also important. And certainly in some organs shape is VERY important, such as the shape of the valves in the heart or the alveoli in the lungs. On reflection, one can probably think of many other examples where the shape determines much about the functioning of parts of organs and cells. Sperm cells have a tail that is their only means of locomotion, for example.
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