Monday, September 10, 2012

The Construction of the Nervous System


As all these operations continue, one more important formation must take place: the central nervous system. The central nervous system (the brain and the spinal cord) arises from an elongate thickening of the ectoderm, the outermost of the three primary germ layers of the embryo. The sides of this neural plate elevate as neural folds, which, by growing further, meet and fuse, thereby creating a neural tube. The anterior part of this tube thickens and expands to form the brain; in the meantime, the posterior part forms the spinal cord.
All the developments we have summarized here in one or two sentences surpass the limits of human imagination. The other stages in the formation of the nervous system again and again confirm the extraordinary character of these developments.
From the fifth week there begins to be produced in the spinal column special nerve cells called neurons. They are produced very quickly at the rate of 5000 per second.41
A large number of brain cells are produced in the first five months of the embryo's life, and all of them will have taken their place in the brain before birth. Cells of the nervous system form very quickly and then begin to migrate to more distant areas in order to form the columns of the central nervous system.
But, at this stage, it is absolutely necessary for every neuron to find the place in the nervous system reserved for it. For this reason, a guide is indispensable in order for the young neurons to find their way. These guides are special cells which stretch out as a kind of cable between the places where the brain and spinal cord develop. The neurons leave the place where they were produced and migrate attached to these guides. They recognize the place allotted to them, lodge there and immediately send out extensions establishing connections with other neurons.
This is all very well. But how do the neurons know to set out on such a long journey as soon as they are formed? How do they decide to use a guide to reach their target and to cooperate with one another? What we call neurons are cells, too small to be seen with the naked eye, and are composed of atoms and molecules. No doubt they cannot deploy in such a conscious way by their own decision or will. What directs this activity is not the brain, because the brain of the embryo in the mother's womb has not yet developed.
As soon as these cells are formed, they move as if programmed, directed by information infused into them, to a place they do not know. It is clear that in the process of the formation of the brain and the nervous system, no occurrence can come about by chance, because a variation in one single stage would cause a chain reaction making the whole system go wrong. The formation of neurons and their becoming a system of nerves is only one stage in the formation of the brain and the nervous system attached to it. Let alone the brain, as the evolutionists claim, not even one neuron can be formed by coincidence.
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O man! What has deluded you in respect of your Noble Lord Who created you and gave you an upright form and proportioned you? In whatever shape He willed, has He moulded you.
(Qur'an, 82: 6-8)

There are many more details of this development. For example, when they first come to be, the neurons have a different structure from those of a mature human being. In order to perform the functions required by the nervous system of a developing human being, the neurons migrate to a particular part of the body, and in the first stage, their metabolism enables them to survive without oxygen. However, when they arrive at the brain area and establish themselves there, they immediately acquire a metabolism that depends on oxygen for its survival. For the benefit of all the nerve cells this transformation must take place perfectly every time, otherwise their survival would not be possible. This is no doubt a miraculous thing.42
We know today that it is highly dangerous for human brain cells to remain without oxygen for a certain period, and if that period be prolonged, first paralysis, then death are inevitable. But the neurons which first come into being have a totally different system. If there is a problem at this stage only, that is, if there is no change in the metabolism of the neurons at exactly the right moment, the embryo will not develop into a human being. Of course, it is not possible for a cell to determine what function it will perform in the future and to change its structure by its own will and conscious awareness in order to perform this function.
This being the case, we are confronted by a clear truth: it is God Who creates the neurons with these characteristics, puts them to work at the right moment and places them where they must go. Every human being should know that he has been brought through these stages, and give thanks when he sees the magnificence with which God has created him as a human being. He must not for one moment forget that God is the Creator of everything, and that apart from Him, there is no other power on heaven or on earth.
... Do you then disbelieve in Him Who created you from dust, then from a drop of sperm, and then formed you as a man? He is, however, God, my Lord, and I will not associate anyone with my Lord. (Qur'an, 18: 37-38)

1 comment:

  1. Great essay and great Citation from Holy Quran,found very helpful for my class Exam

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