The Evolutionary Journey of the Chromosome-To-Be to Its Present Position
No illustration is here given of the Interphase and Telophase as it is deemed unnecessary for the explanation of this subject.
Here greater emphasis is placed on the Chromosome in the course of its evolutionary journey to reach the position of the Metaphase plate during the Metaphase, while ignoring the evolution of the inner part of the Chromosome-to-be and the evolution of the core. (see The Core of the Cell-To-Be turning into a Centrosome).
To ease comprehension, all explanations related with illustrations 1 through to 4 concern only two Cromatids (one Chromosome).
Notes on Illustrations 1 to 5:
1a. In one Cell-to-be there is one DNA-to-be (drawn as red broken lines) of which the interior sticks to the core (drawn as black balls); the tip, which is at the skin of the Cell-to-be, is depicted as resembling a jigsaw puzzle. This was the first division that took place naturally when no replication followed the division of the DNA-to-be. The DNA-to-be was then not yet inside the Chromosome-to-be. In this event the cell-to-be was still inside the activated Carbon particle.
1b. With the core having been divided, the compounds divide themselves too, starting from the lower part (the core). This causes the left DNA-to-be (m) to look as if it were moving clockwise, as its upper end is being pulled by the right DNA-to-be. In contrast, the right DNA-to-be, being in the midst of attempting to divide itself, remains attached to the end of the left DNA-to-be, consequently causing it to look as if it were moving counter clockwise. This is almost similar to events in the Prophase, except that here the DNA-to-be, which was then not inside the Chromosome-to-be yet, as in the Prophase events of today. Here two events occurred: the natural event during which the Rayleigh waves caused the core to split apart first, followed by the chemical event during which the various compounds, including the DNA-to-be, were dismantled.
1c. While the division is still in progress, the lower part, then already divided, attempts to separate all other parts. Despite its effort, it still has not managed to separate the upper part yet such that what results is a form very much like that shown in illustration 1c.
1d. As can be seen in the illustration, though the DNA-to-be finally separates itself, the two daughters-cell-to-be remain attached to each other. This is because inside the body of the cell-to-be there exist various other compounds that are not strongly bonded to each other (Cytoplasms-to-be). Such a condition does not, however, last long. With the various compounds being subject to the dismantling process, the whole cell-to-be eventually splits apart.
1e. Even after it divides and while both of its separated parts are still in one and the same Cell-to-be, the DNA-to-be is, due to its elasticity, inclined to return to its original position. However, as this elasticity—even at its utmost degree—is never one that is perfect, a change of position is therefore always inevitable. The process of evolution depicted here being one that is accelerated, the DNA-to-be as shown in illustration 1 is envisaged to have undergone evolution. During the process, it is not only its position that is subject to change but also its inner parts, though gradually. Thus, the DNA-to-be, which at its initial stage was attached to the core/centre of activated Carbon particle, has separated itself from the core/centre of Cell-to-be. (No illustration is given here of the evolutionary change that occurs when the DNA-to-be frees itself of the core). After the division of the Cell-to-be, the DNA-to-be manages to recover half of its missing compounds, as though replicating itself. The Cell-to-be has now regained its DNA-to-be intact, though in a position set anew. Here it could be said that the process of the re-multiplication of the various missing compounds is done chemically.
2a. This, in fact, is a repetition of illustration 1e at the point when the division is about to be repeated. As in 1b, a change of position also occurs in 2b due to the limitations in the DNA-to-be’s elasticity.
2b. That is why in those DNA’s-to-be compounds that are to be dismantled, the tendency is to take a somewhat rightward position. Compared with 1b, 2b looks straighter.
2c and 2d. The dismantling of the compounds occurs completely chemically.
2e. Both “daughter-Cells, having been totally separated, will each reconsolidate the various compounds it has shared with its “twin sister.” This is done, as illustrated in 1e, chemically—similar to Anabolism. In illustration 2e, given the limitations in its elasticity, it appears to be somewhat different from what is shown in 1e, i.e. straighter. The DNA-to-be is then beginning to place itself inside the Chromosome-to-be.
3a-3e. Here things are not much different from what is depicted in illustrations 2a- 2e. The only difference is that the position is straighter in 3b, 3c looks more like the Metaphase plate line, 3e. also straighter. This, however, does not mean that no change occurs in the Chromosome and the DNA. Here greater emphasis is placed on enabling better understanding of the course taken by the Chromosome-to-be in its journey to the Metaphase plate.
4a – 4d. Here the Metaphase events developed the way they are today. The DNA-to-be in the Chromosome-to-be had already positioned itself in the Metaphase plate’s (imaginary) line.
In Illustrations 2c, 3c, and 4c, on entering the Metaphase, 2b, 3b, and 4b gradually move toward the Metaphase plate, the way it occurs in the present day Cell. All this occurs due to fact that anything that exists in the world, no matter what it is, may after continual usage gradually lose its elasticity. As it would be extremely difficult to present explanations about these things as they actually are, the explanations given here are thus confined to only what is portrayed in the illustrations.
In reality, however, at the time when there occurs a movement towards the position of the Metaphase plate, there also occurs a change of position between the core and the Chromosomes. As already explained above, while the core pulls itself out, the Chromosomes gather at the Nuclear. Apart from this, inside the Chromosomes-to-be themselves there also ensue evolutionary changes.
Illustration 5 represents additional explanations about events taking place at the mitosis stage currently underway.
Illustration 1e through to 4e depict the journey made by the cell-to-be soon after it has manages to free itself from the ACP. The process it performs during metabolism is one that is chemical. The nature process is one that it performs during its evolutionary journey.
What is it that has enabled the Chromosome-to-be to move towards the Metaphase-plate?
The DNA-to-be is depicted to look like pieces of a jigsaw puzzle, which can be put together and taken apart easily (illustration 6).
The change in elasticity leading to a change in the position of the Chromosome-to-be is an indication of the presence of an extremely slow-running process—commonly known as evolution—in living creatures.
Illustration 7 shows a spring of high quality, free of any degree of tension, at room temperature, with the black points a and b at a distance of, say, 10 mm from each other. Now, stretch the spring so that the distance between a and b is seven times its original distance; then, unstretch it so that it returns to its original position. Needless to say, even the best of springs that one could find in this world will invariably be metal fatigue after billions of times of repeated stretching and unstretching.
Being fatigue, each time it gets back to its original position, the distance between a and b will, depending on a number of factors, grow longer, perhaps by 10%, 1%, or 0,1%. However, one thing is certain: there is just no way by which the spring could, in absolute terms, get back to its original position, particularly after billions of times of stretching and unstretching. Because if the spring is pulled even only once, it must stretch, through possibly by only one Angstrom. Now, what if it is stretched millions of times? Certainly its end-to-end distance will become much longer.
Let alone the Chromosome-to-be, whose elasticity is known to be no better than that of the spring. Repeatedly shaken and juggled by the millions of times of division, there certainly is no way by which it could avoid changing its position. Thus, it should not be surprising if all those Chromosomes should, sooner or later, be in the imaginary line of the Metaphase plate. The Metaphase plate position is the last of the series of changes in position occurring in the long process of evolution of the Chromosome. Further evolutionary changes in position may happen if in later days there occurs a drastic change in the body of the Cell.
(Relate this with the forthcoming Chapter)