Bigotry: The Dark Danger
The Miracle of Electricity in the Body
The Heart: Our Bodies’ Electronic ClockOne of the factors that keep you alive at this moment is the blood circulating in your veins. In contrast to any other fluids in the body, blood has functions that require intelligence and consciousness. Heading the list of these functions is distributing the energy that trillions of cells require to live. The defense system that protects the body from germs, the system that collects wastes and expels them from the body, repair and maintenance of the tissues, the establishment of communications and regulation of body temperature are all made possible by the blood. The propulsive force that propels this vital fluid to reach every cell in the body is provided by the heart. In order to grasp the importance of the heart's very special pumping system—another component of the body's electrical system— a closer look at the properties of the blood is needed. Blood, The Source of Human Life, Cannot Have Emerged By ChanceWe are indebted to this fluid that constantly circulates through our bodies, for our living healthy lives. Blood’s most fundamental duty is providing the oxygen that cells need to live, by circulating from the deepest folds of the brain to the outermost layers of our skin. Cells need oxygen to produce energy by breaking down sugar. If blood fails to reach a cell, it suffers oxygen deficiency that leads to the death of that cell. However, this system functions at every moment and in a flawless manner for each of the 100 trillions cells in the body. In one day, the blood travels a total of 19,000 km (12,000 miles)—that's four times the distance across the US from coast to coast. Five liters (1.3 gallons) of blood must circulate in the veins running through all parts of a body of average weight. If a fifth of this portion, a one-liter quantity, is absent, the remaining blood becomes more difficult to move. If it is unable to fill the veins, then the very fine blood vessels will adhere to one another. Blood circulation will slow, and cells will rapidly begin dying. Cells can withstand oxygen deficiency for only one or two minutes. For this reason, the body’s oxygen needs to be constantly monitored and kept at a fixed level. It is definitely illogical to maintain that blood cells acquired such ability by themselves, as the result of chance and possess the consciousness to perform a series of calculations and constantly fulfill this function flawlessly. This is just one of the many features of the human circulatory system. Blood carries nutrients to cells with wholly different responsibilities, and transports their collected waste products to the kidneys, lungs and liver. It receives hormones secreted by the glands and transmits them to organs in need of them. It keeps the body temperature constant and protects the body when any foreign substance enters. In addition, it carries out all these processes without interruption for an average of 70 years. (For detailed information, see Harun Yahya, The Miracle of the Blood and Heart) On the other hand, the body’s organs need various substances in order to perform their own functions. These substances which are carried by the blood include nutrients such as glucose, amino acids, vitamins and minerals and, most important of all, oxygen. That so, you can once again see the importance the veins stretching all through the body, of blood reaching everywhere in it and flawlessly performing all its duties. These substances carried by the blood are of vital importance to the survival of all the body’s organs.
However, not all organs require the same amount of blood. Those with a high rate of metabolism, for example, require more blood than others. Therefore, there is a regulation in the level of blood transfer that, however, does not function like a pre-programmed machine. In extraordinary circumstances, blood circulation alters its way of working according to the situation. In the event of poisoning, for example, the amount of blood flowing to the poisoned tissues is increased, to increase oxygen and remove as much of the toxins as possible. Blood is not limited to carrying oxygen and collecting nutrients. It also collects cell wastes and permits them to be expelled from the body. Each one of your trillions of cells produces many waste products, such as carbon dioxide and urea that collect in the blood and could have harmful effects on the body. But urea is removed from the body by being carried to the kidneys, while the carbon dioxide is carried to the lungs, from whence it is expelled. As you have seen, a very delicate system inside us functions at every moment, according to a flawless plan. But under whose control is it? It is impossible for organs like the heart and liver, consisting of unconscious cells, to accomplish this by themselves. It is equally also impossible for unconscious blood cells to assume such a vital function as constantly carrying oxygen to all the other cells in the body. No doubt that these cells, exhibiting a high level of consciousness that does not belong to them, are working for our survival under the inspiration of God. They fulfill the flawless duties assigned to them. Immune cells are also circulated throughout the body by means of the blood. (For detailed information, see Harun Yahya, The Miracle of the Immune System) The white blood cells, which engage in the first action against bacteria or viruses that enter the body, are carried to the specific location of infection by the blood. Antibodies and leucocytes in the blood immediately identify the place where the danger has arisen and immediately reach their target destination with the rapidly flow of blood. Cells carry out a series of conscious, rational actions, such as recognizing the danger, identifying its location, traveling to the region by means of the circulation and immediately initiating a defense. How does the immune system make its decisions, which require intelligent consciousness? How can it determine that dangers are indeed dangers, and learn how to combat them? These are just a few of the questions that leave evolutionists speechless. The cells in the blood stream are only a few microns in size, and consist of water. They have no reasoning ability, sensory organs, nor any other similar attributes. Yet they can determine direction, identify sickly cells, become aware of danger, and eliminate those dangers by acting in concert—all exceedingly conscious actions. It is unreasonable and illogical to assume that all these functions developed spontaneously, as the result of chance. Blood cells too small to be seen with the naked eye, devoid of any capacity for thought or reason, fulfill all these roles, which you cannot do for yourself, with the greatest care and scrupulousness. Clearly, any phenomenon that did arise by chance would inflict damage on the existing order, rather than improving this magnificent system, because even the slightest error in the body’s microbiological system would have exceedingly undesirable consequences. The Heart: A Matchless PumpThe blood reaches every corner of the body by means of the heart, with its dual pumping mechanism. The two left chambers of the heart pumps fresh oxygen-rich blood to the entire body, while the right chambers send returning blood to the lungs for carbon dioxide to be extracted and replaced with oxygen. The left-hand chambers possess thicker muscles, since they pump at a higher pressure in order to send blood to reach the whole body. The heart’s most important feature is how it works non-stop, beating approximately 70 times a minute, 100,000 times a day, and 40 million times a year.47 During the course of an average lifetime, it beats more than 2 billion times and pumps enough blood to fill an average of 100 swimming pools.
Also exceedingly important is that the heart's indefatigable muscles pump a level of blood that depends on the prevailing circumstances. During sleep, the heart pumps approximately 340 liters (90 gallons) of blood an hour, while during physical activity,—for instance, when running—it increases its tempo to pump around 2,270 liters (560 gallons) of blood an hour. 48 That is because our muscles need more oxygen when performing tiring activities. Under such circumstances, the heart increases its working tempo from 70 to 180 times a minute, and the level of blood reaching the tissues can increase five-fold.
No man-made pump can match the heart's ability to work tirelessly for an entire lifetime and to regulate the quantity pumped according to prevailing circumstances. The extraordinary nature of the heart reveals an important fact. God created many matchless structures, such as the heart, in the billions of human beings. And as revealed in the Qur'an, this is an easy matter for Him: Your creation and rising is only like that of a single self. God is All-Hearing, All-Seeing. (Surah Luqman: 28)
A Matchless Organization of Pumps and ValvesThe pumps in the heart consist of two different sets of pumps, an upper and a lower. The smaller and uppermost are known as the atria and the larger, lower ones as the ventricles. For example, when clean blood reaches the left side of the heart it first fills the small, upper atrium. From here it is pumped to the larger ventricle beneath. The large ventricle sends blood to the organs of the body. The same process is carried out in the pumps on the right-hand side of the heart. Between atria and ventricles are one-directional valves that open to let the blood flow pass. When the small atria contracts, these valves open and blood fills the large ventricles. When the ventricles contract, the valves close between them and the atria, and blood is prevented from flowing back in the direction from which it came. There are similar valves in the large ventricle’s exit. When the large ventricles contract, these valves open and blood is allowed to flow to the body. The moment the contraction stops, however, the valves close, preventing the blood from returning to the heart. This mechanism is exceptionally reliable. Similar systems are employed in modern pumps today. A pump is a device which propels liquids or gasses in one direction. The valve is a gate-like device that opens or closes in order to control the flow of those liquids or gasses. When you pull the trigger on a water pistol, you compress the water inside it. This causes a small valve inside to close and another outside to open, and the piston is pumped, expelling the water. In the same way, valves in the heart guarantee that blood can be pumped in only one direction. The valves in the veins prevent a backward flow against the force of gravity. When you stand upside down, your blood does not rush to your head, as you might expect. That is prevented by the pumps and valves in the heart. We can compare this situation to the way that valves prevent air from escaping after it has been pumped into a bicycle tire.49 As you see, the heart has been specially designed for a specific purpose. And where there is design, there is inevitably a conscious, intelligent designer. Even if we cannot actually see the designer himself, we can see the evidence for his existence by viewing the design. Similarly, the systems in our bodies also reveal the proofs of the existence of our Lord, Who created them all. The Heart’s Electronic System and GeneratorHave you ever wondered what enables your heart to keep beating? How does it work automatically for hours, days and even scores of years? The tireless pumping system works with the electrical energy, as mentioned earlier. The heart transports blood and all the vital materials to the organs and cells thanks to electrical energy. That is the reason why doctors employ electric defibrillators in the event of the heartbeat stopping completely. The energy that allows the heart to beat does not reach it from the outside. Instead, the heart is an engine that produces its own energy used during its pumping process. Electricity is produced by the contraction of the heart muscles. Conductor cells transmit these electrical signals to the muscle cells that are responsible for pumping blood at approximately 70 times a minute. The heart begins beating when the human being is still an embryo in the womb, before any nerves have connected the heart to the brain. The heart is able to continue beating even during heart-transplant operations when all the nerves have been severed and the organ is removed from the patient's chest cavity. Under a microscope, a heart cell even continues to beat by itself as long as fresh oxygenated blood can reach it.50 That is because there is a generator in the heart cells that produce their own energy. As you know, in the event of a cut in the energy supply, a generator is a device that can take over and continue producing energy that prevents machinery from halting or being damaged. The heart, one of the most vital organs in the human body, has also been granted a similar form of protection to prevent its coming to harm, since for the heartbeat to stop for even a moment could lead to serious bodily damage, and might even prove fatal. Therefore, the electrical system that keeps the heart working must itself work without interruption. Scientists investigating its electrical system encouraged some astonishing facts. The heart functions thanks to an ensemble of programmed and systematic electronic circuits, with a great many interconnections. This electronic control-and-management system co-operates with a large number of other organs, from the kidneys to the brain, from the arteries to the hormonal glands. But who or what causes unconscious cells to perform such clearly conscious actions?
The only answer to all these questions, of course, is Almighty God, the Lord of the worlds.
Heart Cells and Electricity ProductionThe cells that contract so tirelessly must possess a design that can begin to work the moment electrical current reaches them. The cells must respond to every single signal that reaches them, on an average of 72 times per minute. If you examine the heart under a microscope, you can count more than a million cells. Exceedingly complex biochemical processes take place in every one of them. Heart cells are nourished by sugar molecules and oxygen coming directly from the lungs. Every cell has its own pumps and channels and is joined to its neighbors by connective tissue.51 Every long, thin cell has a cell membrane that divides the cell from the environment outside and fiber-like proteins that are able to contract. Proteins embedded in the membrane carry important signals or substances from one side of the membrane to the other. In terms of electrical charge, this polarizes the cell, generating a voltage difference between the inside and the outside of the cell. This difference, known as membrane potential, enables certain proteins in the cell membrane, known as ion channels, to function like gates. When they are opened, ions flow in. As a result of complex interactions of ion pumps and channels, a heart cell contracts thanks to the electrical and chemical differences occurring along the length of its cell membrane. Consider a cell in the heart ventricle as an example. At a state of rest, the membrane potential in any cell is more negatively charged than its external environment. However, the electrical stimulus arriving from the neighboring cell rapidly alters everything. This differential suddenly increases, and the sodium channels quickly open up. In this way, sodium ions (Na+) rapidly enter the cell, triggering the opening of the calcium channels. When calcium ions (Ca+2) collect around the cell proteins, these contract. At this point, the sodium and calcium channels close and the ion pumps move the ions outside the cell, causing it to return to its original state. In a healthy heart cell, this transition takes place in less than a second. The events described here are in fact only a very general account of the true state of affairs, which is much more complex in its details. The heartbeat, which requires so many conditions to be met and work together flawlessly, is one of the countless examples introducing us to the knowledge of our Lord. My Lord encompasses all things in His knowledge, so will you not pay heed? (Surat al-An'am: 80)
The Pacemaker That Regulates the Speed of the HeartbeatProduction of electricity by the heart cells is not enough by itself. These cells must first combine in the right sequence, but it is still not enough for them merely to join together. These cells must produce electricity together, in a particular rhythm. Each cell must time itself to act every 0.83 of a second, without fail. Moreover, cells must carry on their activity for an entire lifetime, never tiring. Furthermore, they must know the level of electrical current that will cause the heart to work as a whole, and to produce that current at exactly the right level—neither more nor less. When spread out thinly on a microscope slide, different heart cells will beat at different speeds. But when combined together, they form a single tissue that behaves as a single entity. The same applies to the heart cells in the human chest; although each one initiates its own beat, they all beat in a rhythmic harmony. The pacemaker in your heart contains an internal clock that regulates the speed at which your heart beats. This pacemaker is actually a collection of cells, but it functions far more perfectly that any electronic device. Using conductive fibers, it distributes the electrical current it produces to every point in the heart muscle. But this electricity proceeds at different but controlled speeds. When both heartbeat and transmission system are working properly, they carry out an ordered and determined distribution of electricity. The heart possesses a natural battery that regulates the speed at which it beats—a specialized electrical cell node known as the SA node, (for sinus or sinoatrial node), located in the upper part of the right atrium. These cells initiate electrical impulses that stimulate the heart muscles to contract regularly. The SA node produces the electrical stimuli that spread throughout the heart, ensuring that its four chambers all contract at the proper times. This electrical impulse travels from one side of the heart to the other so rapidly that it gives the impression all the cells are beating at once. This rhythm is the heart’s normal beat, which is between 60 and 100 times a minute.52 It takes 0.3 of a second for the electrical impulse to move from the SA node to the region known as the AV node located between the atria and ventricles, and this is known as the normal sinus rhythm.53 The AV node is the location of the cells that produce the second electrical current that completes the heartbeat.
Just like a sparkplug in an engine, the heart cells fire many times a minute. Each firing passes through a specialized electrical path and stimulates the muscle walls of the heart's four chambers in a specific order. First the upper two chambers of the atria are stimulated, after which there follows a slight delay for the two atria to empty. When the moving electrical current reaches the region between the atria and the ventricles known as the atrioventricular node (or AV node), it slows down a little: The AV node delays the electrical signal by holding onto it for the short space of 1/14 second—an interval of time that is very sensitively adjusted. The AV node's delay gives the atrium time for to contract tightly and send the blood on to the ventricles. This way, the ventricles fill with blood to their maximum capacity before receiving the electrical current, that signals them to pump out their contents. Were it not for this momentary delay, the ventricles would contract before they were entirely filled with blood, and not enough blood would be transmitted to the body. Following this delay, the electrical signal continues on to stimulate the other ventricular cells 1/16 of a second later. The large ventricle, now filled with large quantities of blood and whose turn has now come, contracts and pumps blood in to the body. All these processes take place in less than one second.54 To sum up, the electrical current first emerges in the upper part of the heart, in the SA node, ensuring that electricity is distributed throughout the heart and that the heart's muscle cells contract as it passes moves.55 Yet the situation that comes about is very different from what one would expect under normal conditions. The energy given off by the generator should first stimulate the small atria and then the large ventricles. Yet since the electrical wave moves very quickly, both pumps should contract at almost the same time, and the heart's work would be seriously impaired. Yet this never happens, because all this has been taken into account beforehand. So perfect is the design of the electrical circuit in our hearts that the electrical energy first stimulates the small atria, is kept waiting for a time, and only then stimulates the large ventricles. After the electrical signal has set out, the atria keep it waiting at a specific point until they have fulfilled their functions. But the heart and blood vessels do more than speed up or slow the blood circulation in response to the body's needs. They carry blood to different tissues to spark off different activities. Extra blood rushes to the stomach when we eat, to our lungs and muscles when we run, and to the brain when we think and speak. The heart and circulatory system combine data just like a computer to meet the body's various needs, and thus respond in a way that no computer can.56 The deceleration or acceleration of the heartbeat generally leads to tightening of the chest and discomfort expressed in the form of palpitations. The abnormal acceleration or deceleration of the heartbeat may result from disruptions in the heart’s electrical signals. In order to understand rapid or slow palpitations, we need to examine how the normal heartbeat comes about and acts throughout the heart. In cases where the heart cannot make this adjustment, an electronic pacemaker is used to adjust the speed of the heartbeat. However, these artificial devices bring with them a number of drawbacks that require careful attention. They must not enter magnetic fields, and have to be kept away from devices that generate magnetic fields. Yet no such problems are experienced in the heart’s natural pacemaker. How, then, did a group of cells in our bodies determine—and then meet—needs of which we are consciously unaware? This is a precautionary measure in our bodies, a comfort prepared for us beforehand. All this is just one of the signs of the infinite mercy of our Lord. There is no one in the heavens and Earth who will not come to the All-Merciful as a servant. He has counted them and numbered them precisely. (Surah Maryam: 93-94)
The Accelerator-Brake System in the Heart’s Operations
Most people know that their hearts speed up under certain circumstances—as when they quickly climb a staircase, run or become excited. The heartbeat speeds up, returning to its normal rhythm later. However, most people fail to realize what a great miracle this actually is. The speed of the heartbeat is regulated by a natural computer system installed inside the body. When heartbeat accelerates, unless the body is provided with sufficient oxygen, the cells lose their electrical equilibrium and begin beating fast and irregularly.57 For that reason, it is of the highest importance that the heart should beat constantly at a regular rhythm. Like a car traveling at a fixed speed, the heart’s tempo also needs to be speeded or slowed in certain situations. The “brake pedal” that slows the heart’s rhythm is the vagus nerves, and the throttle that speeds it up is the sympathetic nerves. 58 A messenger molecule called acetylcholine permits the braking action. The heart normally beats 72 times a minute. In situations that place a strain on the heart, when a person is under stress or running a fever, the SA node speeds up since the tissues need the heart to pump more blood. In this way, the sympathetic nerves raise the blood pressure by narrowing the blood vessels, and the adrenaline glands over the kidneys release the hormones adrenaline and noradrenalin, which increase the speed of the heartbeat. The hormone thyroxin released by the thyroid gland affects the workings of the heart by speeding the metabolism.59 The heartbeat can rise to five times its resting level. The sympathetic nerves speed up the heart like the throttle in an automobile. When the parasympathetic system is needed, it can slow the heartbeat to 40 beats a minute by easing the force with which the heart muscles contract.60 When they detect that the blood pressure has risen, receptors in the arteries stimulate the brain by means of the parasympathetic nerves to release the chemical known as acetylcholine. Blood vessels in the heart expand, and thus pressure falls. If the blood vessels carrying clean arterial blood were not wide enough, they might tear and rupture. The skull might then fill with blood as in a stroke, and the individual be crippled by lack of blood reaching the brain.
But how does this assortment of cells know when to beat, and how fast? Who tells them to adjust their speed? And how did they acquire the consciousness with which to carry out such a vital function? How and by whom is the decision to accelerate or decelerate taken? In the human body, there is such perfect regulation and such a network of data-exchange that no artificial processing network can begin to compare with it. This system functions without your knowledge, even at this very moment, showing that it is the product of a superior Intellect and Knowledge. These belong to our Lord; Who is capable of creating whatever He wishes. Whenever you do something that requires effort, the muscles around the veins accelerate the flow of blood returning to the lungs. This means that more blood flows to the right atrium in the heart. At this instant, the muscles contract. The central nervous system transmits the nerve signals that form as a result of this tension to the medulla oblongata. The medulla analyzes these data and sends a command to the heart, whose accelerator is activated and its rhythm speeded up. More clean, oxygenated blood thus reaches the muscles. To keep the heart from beating so fast as to damage itself, a special security mechanism is needed. The aortic veins emerging from the left side of the heart contain receptors that measure blood pressure. As the heartbeat speeds up, the pressure of the blood against the aortic wall rises. When this exceeds a particular level, the receptors become aware of the rising pressure and send messages to the spinal cord bulb, which again evaluates the situation and sends a new command to the heart. At this, the rhythm of the heart is slowed, and the blood pressure is lowered. It is completely incompatible with logic to maintain that unconscious cells know that a too-rapid heartbeat will harm the body and take precautionary measures to prevent it—or that these cells came into being by chance. Namely:
These and many other actions requiring intelligence and consciousness cannot possibly result from the chance cooperation among unconscious atoms. This flawlessly functioning system was created with the knowledge and artistry of our Lord, Who enfolds and surrounds all places. Sympathetic nerves: components of the autonomous nervous system that work outside our conscious control and regulate the workings of the internal organs. The Emergency Signal
The human body sometimes needs to be stronger, more resistant and to exhibit a higher performance than normally. For example, when a person has to defend himself or escape, the heart needs to beat faster and to pump more blood. For situations like these, the necessary precautions have been taken, and another system has been installed in the human body. In case of any extraordinary situation, the adrenal glands secrete the hormone adrenaline. In comparison with its size, this hormone molecule makes a very long journey to the heart. Reaching there, the hormone commands the heart cells to contract more speedily. The adrenal cells producing this hormone know which language those heart cells will understand. At the same time, they are aware that the body must be more resilient and therefore, the heart needs to beat faster. The heart cells obey this command and begin beating faster, and in this way, the body is provided with more of the oxygen it needs in emergency situations. The famous Israeli physicist and molecular biologist Gerald L. Schroeder refers to this special system: Muscle cells and especially muscle cells of the heart have large numbers of receptors designed to pass adrenaline, a stimulant hormone. At the sensation of danger (sensation did I say? I wonder just which carbon atom is experiencing this emotional trauma?), our reptilian response of fight stimulates the release of large doses of adrenaline in to the blood. Taken up by the heart muscles, the beat increases dramatically, pumping oxygen-rich blood to power hungry muscles in arms and legs. Cells along the small intestine are constructed to absorb glucose, amino acids and fatty acids, the products of food digestion and transport these products to the adjacent bloodstream, where they'll be carried to the membranes of cells. 61 As you have seen, it is astonishing how cells made up of unconscious atoms immediately identify this danger, declare a state of emergency, and take the relevant measures. This series of events requires consciousness and cannot, of course, be the work of chance. Our Almighty Lord created all of these cells and inspires in them the knowledge of what to do, and when. All Factors must Be Present at OnceIn order for your heart to work with perfection, it needs electrical signals. In order for those signals to be produced, the sodium, potassium and calcium ions need to be present at particular levels in the blood. Bearing in mind that these levels are regulated by organs such as the kidneys, intestines, stomach and lungs, it's even more evident that such a system cannot be the result of a fictitious mechanism such as evolution. First of all, there is a technology in the heart far superior to that of any man-made device. But most important of all, is that there would be no purpose for the heart to come into being by chance on its own. Together with the heart, there must be blood vessels thousands of kilometers (miles) in total length, as well as liquid blood to fill those vessels, kidneys to filter the blood, lungs to give oxygen to the blood and absorb carbon dioxide, a digestive system to provide nutrients for the blood, a liver to refine these nutrients, a nervous system to regulate the working of the heart, a brain to manage the body as a whole, a skeletal system to keep the body upright, and a hormonal system to assist the heart's operations—are all present at the same time. The way that all these and thousands of other elements come together in the most harmonious manner possible is one of the many proofs of a flawless Creation.
Footnotes47. Dr. Sue Davidson, Ben Morgan, Op cit.,2002 48. Marshall Cavendish, The Illustrated Encyclopedia of the Human Body, p. 70. 49. Lionel Bender, Human Body, Science Facts, Crescent Books, New Jersey, 1992, p. 34. 50. “The Incredible Machine,” p. 123. 51. Mark Buchanan, “The heart that just won't die,” New Scientist, Vol. 161, no. 2178, 20 March 1999, p. 24. 52. http://sprojects.mmi.mcgill.ca/cardiophysio/AnatomySAnode.htm 53. Ibid. 54. Marshall Cavendish, Op. cit., pp. 74-75. 55. http://www.healthandage.com/Home/gm=2!gid2=2089 56. “The Incredible Machine,” p. 124 57. “The Incredible Machine,” p. 154 58. Curtis&Barnes, Invitation to Biology, New York: Worth Publishers, Inc., 1985, p. 415. 59. Vander, Sherman, Luciano, İnsan Fizyolojisi (Human Physiology), Bilimsel ve Teknik Yayınları Çeviri Vakfı, 1997, pp. 222-228. 60. “The Incredible Machine,” p. 128. 61. Schroeder, Op. cit., p. 64. |