Monday, September 10, 2012

The Egg Cells Begin to Develop...

The egg is produced in an organ with every aspect having been especially designed for this purpose: the ovary. In every woman, there are two ovaries, one on the right and one on the left. In these ovaries, there is a space, big enough for nerve fibres and blood vessels and lymphatic ducts to enter and exit. Inside this space, there are fibrous tissues rich in blood. For the egg cells to be formed safely, they must be nourished and protected by these tissues. Within this protective structure, there are many sacs (follicles) of varying sizes. In every follicle there is one primary egg cell. But only a single mature ovum is normally released from the ovaries each month so that only a single foetus can begin to grow at a time.

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But this production does not consist of only one stage. In order for this egg cell to mature, a few developments must occur, one after the other. In order for the primary egg cell to maturate and become reproductive cells, one division by mitosis and two divisions by meiosis must occur, and in a definite series without confusion. As a result of the divisions, a difference in the number of chromosomes in the cell occurs and different types of cells are formed. As is the case with male reproductive cells, in the female, too, the 46 chromosomes in the primary egg cells are reduced to 23.
As a result of the divisions by mitosis and meiosis in the egg cell, three small cells and one large cell (ootid) are produced. The small cells die from lack of nourishment, while the large cell undergoes some changes and becomes the egg. If each of these cells were the same size, there would not be enough of the required nourishment for the development of the zygote at the end of the fertilisation process. But the fact that one of the cells has more nourishment, and the others are small prevents such a problem from developing.
The development of the egg is not an unchecked phenomenon that occurs randomly by itself. As we explained at the beginning, what gives shape to this development, as in the case of the male reproductive system, are the hormones secreted by the pituitary gland, which is located under the brain. It is possible to outline the stages in the formation of the egg and the hormones involved in the process:
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1. Follicular Growth: This is the stage in which the egg cell begins to be formed. The primary egg cell is found, as we said before, in what is called the follicle. The formation of the follicle takes about 14 days. A pituitary hormone, FSH (follicle stimulating hormone), comes to the ovaries in the bloodstream. This hormone is responsible for the formation and development of the follicle in the ovaries and the production of the egg from the primary cell in the follicle. At the same time, this hormone is the cause of the secretion of the oestrogen hormone from the mature follicle. Oestrogen is a hormone which especially affects the uterus. It accelerates the division by mitosis of the cells in the uterus; this area then swells forming a soft cushion to which the embryo will adhere after the process of fertilisation. In addition, it ensures that a sufficient quantity of blood and tissue fluids are directed to the uterus. These preparations are made every month. If an egg is fertilised, it lodges in this specially prepared tissue where it is nourished and its development continues.
As is the case at every stage of human creation, here also a miraculous event takes place. The cells in the female reproductive system determine in advance the needs of the embryo that they will host, make preparations to meet these needs and work to supply the most suitable environment for the development of the foetus. How can a collection of cells effect operations that require such a degree of consciousness and intelligence? It is, of course, impossible to say that cells possess such a consciousness and intelligence, but cells in the female reproductive system (even cells in the pituitary gland) do these things which we have declared impossible for them, and prepare in advance the environment most suitable to the needs of an embryo they have never known.
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It is not possible for anyone with an intelligent mind to claim that cells do these things by their own will and intelligence. Indeed, only one whose thinking is seriously flawed could claim that cells composed of unconscious atoms can do what he himself cannot possibly do with his conscious intelligence. This being the case, the reality before us is crystal clear: all the cells that contribute toward the creation of a human being perform their functions by the inspiration of the Creator; they are vehicles in the realization of a miracle that occurs when every human being comes into the world.
2. Ovulation: At this stage the follicle that carries the egg breaks and the egg is released. But the egg cell, which has been released from the ovaries into the void needs assistance. Otherwise, the egg cell would never be able to find the place to meet the sperm. So, at this point, the fallopian tubes, located between the ovary and the uterus, go into action. The egg cell, which has been released from the ovaries into the void, is caught by the fallopian tube, which has large tentacles like an octopus. The fallopian tube provides an appropriate environment for fertilisation and the later stages occur depending on whether or not there are sperm present in this tube.
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Controlling all this process is the luteinizing hormone (LH) secreted by the pituitary gland. It is worthwhile pointing out another interesting thing about this hormone. The LH hormone is absolutely necessary for the breaking of the follicle in which is located the mature egg cell and for its movement toward the place where it will meet the sperm. The absence of this hormone will result in the failure of the follicle to progress to the stage of ovulation, even if there is no deficiency in the secretions of the other hormones. But this sort of problem does not occur and 2 days before the ovulation stage, for a reason that scientists are still unable to explain, there is an increase in the secretion of the LH hormone from the anterior pituitary gland. At the same stage there is an increase in the FSH hormone and, by the influence of these two hormones, ovulation occurs regularly every month. In other words, here too the pituitary gland makes an astounding calculation of time and begins the secretion of the required hormones at exactly the right time and in the proper quantities.
Of course this conscious activity is not to be expected from the pituitary gland itself or from the cells which make up this gland. Since there is a superior intelligence and will to be seen here, there is One to Whom this intelligence and will belong: it is the intelligence and will of God which reveals itself in all of these wondrous occurrences in the stages of human creation.
3. The Corpus Luteum (yellow body) – The Luteal Phase: After expulsion of the egg from the follicle, the empty follicle fills with blood. There are special cells called "granulosa" and "theca" cells, which surround the empty space where these follicles are located; they multiply and take the place of the clotted blood in the follicle. These cells accumulate yellow lipid, and are therefore called lutein cells, from the Latin word luteus, "saffron-yellow." So, the follicle from which the egg has been released swells with the fluids which have filled it and becomes an active element called the corpus luteum (yellow body).15
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The corpus luteum plays an important role in the preparation of the uterus for the embryo and in conducting the pregnancy in a healthy manner. The most important particularity of this element is the secretion of the hormone called progesterone under the influence of LH (luteinizing hormone). Progesterone has an extremely important function in stimulating the walls of the uterus. The most important change in the uterus occurs in the mucous membrane (mucous) that lines the uterus. Under the influence of oestrogen and progesterone, the mucous membrane begins to swell. The glands and blood vessels become highly tortuous, and the thickness of the uterine wall increases. The purpose of these changes is to prepare a suitable place for the embryo after fertilisation. In addition, it allows the pregnancy to advance by making the walls of the uterus relax. Progesterone also affects the development of the milk glands.
That one hormone can have an influence on another and that they have the sense to do these things exactly at the right time cannot be explained by the operation of chance. This brings some questions to mind: How can a molecule formed of unconscious atoms be possessed of such a sensitive innate power and take the initiative to organize the operations of the body so comfortably? It is clear that the molecules that make up the hormones do not have intelligence or consciousness. This shows that the system together with its complementary character has been created by a supreme power. It is God, Lord of earth and heaven Who has inspired the molecules which compose the hormones and the atoms which compose the molecules in their conscious activities.
The corpus luteum phase lasts 12-14 days. At the end of this period, if fertilisation has not taken place, the corpus luteum degenerates and the same stage is repeated. With the degeneration of the corpus luteum, oestrogen, progesterone and other hormones are no longer secreted; that is, the pituitary gland again comes into action. Once again the secretion of FSH and LH begins in the pituitary gland, causing the growth of new follicles to begin. But these follicles cannot develop sufficiently because the lack of oestrogen and progesterone causes a new stage to begin—menstruation.
It was He Who created the heavens and the earth in all truth. The day He says "Be!" it is. His word is the Truth. All sovereignty shall be His on the Day the Trumpet is blown. He is the Knower of the Unseen and the Visible. He is the All-Wise, the All-Aware.
(Qur'an, 6: 73)

4. Menstruation: This is the stage in which the unfertilised egg is ejected from the body. Because fertilisation has not taken place, the previously prepared wall of the uterus contracts, the blood vessels are constricted and the egg is ejected. After this stage, the body will begin again to prepare to carry out all these functions.
This whole stage is repeated in all women regularly throughout a particular period of time. Every month new egg cells are produced, the same hormones are secreted again and again at the same period and the woman's body is prepared as if fertilisation were going to occur. But in the final stage, the direction of the preparation changes according to whether or not sperm are present.

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