1. Hypothalamus |
While you read these pages, countless processes take place in your body without any trouble and you don't feel anything reflecting their true complexity. The number of times your heart beats in a second, the rate of calcium in your bones, the sugar level in your blood, the amount of water your kidneys filter every minute and many other details like these are realized as the result of the harmonious working of the cells in your body. Not just a hundred, a thousand or a million of them; there are about 100 trillion cells in your body. What, then, provides the harmony among this number of cells? The answer is, your body's hormonal system.
The pea-sized pituitary gland controls and regulates the production of many hormones throughout the body. It also oversees the other glands and keeps hormone levels in check. It works under the control of the region of the brain called the "hypothalamus." The pituitary gland looks like a piece of meat. It senses, because of data coming from the hypothalamus, what is needed in which circumstances. It determines which particular cells of which particular organs need to work to fulfill these needs, the chemical mechanisms of these cells, their physical structures, the products that need to be produced and the time when the production of these products needs to be stopped. In addition, by means of a very special communications system, it gives commands to all necessary units for these needs to be met.
For instance, the human body develops until the end of adolescence. Trillions of cells multiply by dividing, thus the growth of tissue and organs is accomplished. When a certain size is reached, the growth activity in the organs stops. It is the pituitary gland that senses how much we need to grow and which stops our growth when we reach the appropriate size. The pituitary gland adjusts, at the same time, the metabolism of carbohydrates and fat in the body. When needed, it increases the production of protein in the cells.
If you feel dizzy or experience some kind of distress, you only have to rest for a while and your distress should disappear. If the cause of this distress is a fall in your blood pressure, the pituitary gland reacts immediately. The molecules secreted by the pituitary gland cause the muscles around the veins to contract. The contraction of millions of muscles and narrowing of veins increases the blood pressure and makes you feel better.
The pituitary gland is only one of the regions where hormones are secreted all together. In addition, regions such as the thyroid gland, parathyroid gland, adrenal glands, pancreas, ovaries and testes secrete very important hormones for the continuity of life. If there is a loss or impaired functioning in any of these regions, the continuity of life becomes impossible. The hormonal system, like other systems in the body, works in perfect harmony. It is undoubtedly Allah, the Almighty, Who provides this unity and has created this perfect communication system in the human body.
1. Hücre Zarı Detayı |
Think of a building where very strict security measures are enforced; nothing harmful is allowed to enter, extraordinary controls are exercised and only then may newcomers be admitted. Yet, suppose that this building performs these functions all by itself. Suppose it acts like a living organism without any interference or assistance. With today's technology, it might be possible for a building to act like a conscious entity, in other words, to execute security controls using the aid of computers and do identity checks. What, then, would you think if we tell you that such a system actually already exists in a place which measures only one-hundred-thousandth of a millimeter? Even with today's technology, such an achievement is clearly beyond us. Yet, this does not mean that such a system does not exist anywhere on Earth.
This extraordinary system, which you might imagine impossible when you hear of it for the first time, has existed since it first came into being. Such a system already exists in the membrane of every one of the approximately 100 trillion cells which make up the human body.
The cell membrane demonstrates characteristics such as making decisions, remembering, and evaluating, which are some of the basic features of human beings. It maintains connections with adjacent cells and also controls incoming and outgoing cell traffic in a very sensitive way.
Because of its great decision-making skills, its memory and the wisdom it shows, the cell membrane is considered to be the brain of a cell. Yet, the cell membrane is so thin that it can be detected only by using an electron microscope. The membrane looks like a two-sided wall. This wall is equipped with gates that enable getting in and out and with receptors that enable the membrane to identify the outside environment. They are located on the cell wall and cautiously control all traffic.
The first job of the cell membrane is to keep the cell organelles together by wrapping around them. In addition, it provides necessary substances from outside in order to enable these organelles to function properly. While doing this, the cell membrane behaves very economically; it does not let in a greater amount than it needs. It determines harmful waste material without losing time and expels it right away. The role of the cell membrane is very crucial; it does not accept the slightest error, as any error or defect means the death of the cell.
It is obvious that such intelligent acts and conscious decisions of the cell membrane, a layer composed of lipids and protein molecules, are not generated by itself alone. Anyone who possesses wisdom and consciousness can easily see that that such a system cannot originate by chance. Both the cell and the membrane that covers the cell have been created by Allah, the possessor of ultimate knowledge. And they serve the purposes that Allah, Who has created them perfectly, has determined for them.
DNA is the database of the human body. Take a look at people around you and try to think for a moment about what kinds of characteristics they have. In fact, the color of their eyes, their height, the color and type of their hair, their voice, and the color of their skin and all such data is recorded in their DNA. This database contains all kinds of information about the structure and needs of both the cell in which it exists and of all other cells in the body. Comparing the human body to a structure, we find a complete blueprint of the body, including each and every detail, not excluding the slightest, in the nucleus of every cell within DNA.
DNA is carefully protected in the nucleus in the center of a cell. When one remembers that the average diameter of a cell is one-hundredth of a millimeter, one can better grasp an understanding of how small a region is being discussed. This miraculous molecule is clear evidence for the perfection and splendor of Allah's artistry in creation.
The information contained in DNA not only determines physical characteristics but also controls thousands of different processes and systems in the cells and the body. Having either low or high blood pressure, for example, depends on the information contained in DNA.
Scientists have advanced different theories in order to emphasize the amount of information contained in the genetic structure of man. The information in DNA is so plentiful that if books containing this information were stacked one on top of each other, they would reach sky-high, all the way to 70 meters (230 feet). Scientists have also calculated how long it would take to type the gene map of a human and they concluded that a person typing 60 words per minute and working 8 hours a day would take fully a half-century to complete this momentous task. They also stated that approximately 200 telephone directories of 500 pages apiece could be filled with the information contained in DNA.
A chain made up of atoms lined up side by side, each having a diameter of one-millionth of a millimeter, has such an immense amount of information and memory that a living creature can use it to carry out all its life functions. This is evidence for creation. With the information He put into DNA, Allah once again presents His boundless power and the fact that He has no partner in creation. The boundlessness of Allah's knowledge is related in a verse with the following comparison:
Say: "If all the sea was ink to write down the Words of my Lord, it would run out long before the Words of my Lord ran out," even if We were to bring the same amount of ink again. (Surat al-Kahf: 109)
Eğer Allah'ın nimetini saymaya kalkışacak olursanız, onu bir genelleme yaparak bile sayamazsınız. |
Many substances look different and have different features although they include the same atoms. What do you think makes objects around you different? What makes them different in terms of their color, shape, smell and taste, and what makes them soft or hard? The reason for all of these distinctive differences is that their atoms constitute different chemical bonds to form molecules.
Following atoms, which are the first step on the way to substance, molecules are the second step. Molecules are the smallest units which determine the chemical features of a substance. Some of these small structures consist of one or more atoms, but some of them consist of thousands of atom groups. The diversity we see around us arises because molecules come together in different ways. We can see this by giving examples from our senses of taste and smell.
Indeed, concepts like "taste" and "smell" are nothing more than perceptions created in our sense organs by different molecules. The smells of foods, drinks, and various fruits and flowers all consist of volatile molecules, an example of which we see in the small picture on the right. Atoms form living and non-living substances and also give matter its taste and beauty. How does this ever happen?
Volatile molecules like vanilla and tulip scents penetrate the receptors of tiny hairs in the region of the nose called the epithelium and interact with these receptors. This interaction is perceived as scent in our brain. Similarly, there are four different types of chemical receptors at the front part of the human tongue. These correspond to the salty, sweet, sour and bitter tastes. The molecules that come to the receptors of all our sense organs are perceived as chemical signals by our brain.
Today, it is understood how taste and smell are perceived and how they are made. Yet, scientists cannot reach a consensus on why some substances smell more while some others smell less, or why some of them smell bad while some others smell pleasant.
The existence of taste and smell is not a fundamental need for human beings. However, hundreds of kinds of delicious fruits and vegetables, with their enticing scents, and thousands of kinds of flowers with different colors, shapes and smells, all come out of the soil. All of them add a distinctive beauty to our world as products of a magnificent art.
From this point of view, color and smell, like all other blessings, are two of those beauties that Allah, the Most Gracious and Glorious, bestows on people without measure. The absence of these two senses only would be enough to make man's life tasteless. In return for all these blessings given to him, what befalls on a man is certainly to try to be a servant of Allah, Who encompasses him with His knowledge.