Chapter 1: Blood: The Incomparable Liquid of Life (8/10)
Plasma: The Liquid That Enables the Cells to Move
To fulfill their functions, erythrocytes and leukocytes have to travel throughout the whole body. It is impossible for them to do this by themselves, however. Even though cells have various mechanisms that allow themselves to move, still there needs to be a fluid for them to move in. This fluid, which travels to every point in our bodies every second, together with the various forms of blood cells, is plasma.
Plasma constitutes 55% of the blood. It contains 90% water, along with albumin that is used in regulating that water level, globulin used in transporting vitamins, fibrinogen used in blood clotting, glucose and other nutrients, ions used in regulating intracellular fluid pH and levels, fats, amino acids and vitamins, and dissolved gasses such as oxygen, carbon dioxide and nitrogen.54
With the substances it carries and the properties it possesses, plasma performs vital functions in the body, the most important of which is the carrying of nutrients and wastes. Other important features are allowing blood pressure to remain at a specific level, and heat dispersal. In addition, plasma is responsible for maintaining acid proportions at a specific level in other tissues.
Since plasma is the fluid component of blood, its level can decline by 50% during excessive perspiration, or can rise by 60% when large amounts of water are consumed. The water contained in the plasma is the basic element of blood, but there are also solids in plasma, such as proteins. These include fibrinogen, which permits blood clotting (to be examined in depth in the section on blood clotting), the albumin that regulates the level of blood cells and body fluid, and globulins rich in antibodies. From our point of view, it will be useful to examine the highly important albumins.
Albumin: An Intelligent Transporter
In numerical terms albumin is the most abundant protein in plasma and assumes a transport function in the blood. However, albumin is no ordinary carrier. It transports fats such as cholesterol, hormones and the toxic yellow pigment bilirubin, a gall bladder product. In addition, it binds mercury and penicillin and other antibiotics. It releases toxins in the liver and carries nutrients and hormones to the requisite destinations.
The way fats are transported by a protein in the body is of great importance. If fats were not transported by albumin, then all the fat molecules would clump together in the blood and float in an unregulated manner, just like globules of fat in a bowl of soup. That would soon lead to blood-vessel congestion and death.
Hormones are responsible for the distribution of messages in the body; and they too must have a means of transport. It is again the protein albumin transmitting hormones to the necessary locations. If albumin lacked this property of carrying hormones, then no signals, from hunger to thirst, would reach the relevant regions; and all functions concerning the human body, from growth to development, would come to an end. Although it needed water, the body would be unaware of this. Albumin is a protein specially created in order to be able to perform these message-bearing functions and one which literally knows what needs to be transmitted where.
Nor are albumin's duties limited to these alone. Nutrients moving in the arteries have to be able to pass through the tissue walls in order to reach the interior cells. Although the tissue wall has a great many pores, it still permits no substances to pass through it. The main element enabling nutrients to enter the tissues is blood pressure. Thanks to the force of blood pressure, nutrients are able to reach the requisite locations. However, there is also the possibility that the level of substances "pumped" to the tissues by means of blood pressure will be greater than normal. Excessive fluids in the tissues will lead to edema. In order to prevent this, albumin enters the equation as a competitor to blood pressure, pulling liquid back into the blood. Because of its higher concentration of albumin, the blood absorbs water just like a sponge. Were it not for albumin, the body would swell up like a dry sponge left to soak in water.
In the brain, however, substances in the blood need to pass through the vessel walls in a rather different way. The brain is a very sensitive organ, and if the substances in the blood were to enter the brain tissues in an uncontrolled manner, they could damage the neurons. The brain therefore has a very special protection. Tissues in the brain are covered by dense layers of cells. In order to enter, substances in the blood literally have to undergo passport checks as they pass through these cells. Yet even if these substances do clear "passport control," once they enter the brain tissues, they are still not left unsupervised. Specific brain cells are densely packed between the veins and nerve cells and are literally attached to the tissue walls. Substances in the blood can reach the brain cells in question only if they are able to pass this tight security.55
Some organs in our bodies need to be protected more vigilantly than others, and every cell in the body seems aware of this. The main organ requiring protection is the brain. Damage to the brain will lead to problems that impact on the entire body. Anything that damages the brain's sensitive regulation and structure thus means damage to the body's equilibrium. Therefore, this delicate organ is protected by highly detailed, complex mechanisms.
Aware of this special protection, the cells behave very carefully. Because the heart, too, is aware of this delicacy, it pumps blood to the brain in very careful and measured amounts. The sentries in the brain admit substances accordingly, since they are also aware of this sensitivity. In short, every mechanism in the body assumes the task of protecting its central headquarters. All these processes, which have been described in terms of organs and structures knowing about them, are in fact all signs of God's infinite wisdom and knowledge which are manifested in living things. This needs to be constantly borne in mind.
The brain's special protection once again proves that there is a regulated system within the body. Cells, consisting of unconscious organelles, certainly cannot possess such awareness. God protects the brain and the cells that comprise it at every moment and preserves them. This sensitive overseeing continues at all moments. If it did not, lack of control would soon lead to death.
Thrombocytes: The First Agents in Coagulation
Another important element in the blood, thrombocytes, or platelets, are cells charged with the initial repair of damaged tissue and initiating a series of events so that the blood in that region can clot. Thrombocytes live in the blood for 7 to 9 days. Their total volume in the bloodstream is very small, however: The human body contains no more than a teaspoonful of thrombocytes.56
In fact, thrombocytes are not real cells at all. Colorless and lacking nuclei, they consist of particles that separate from the bone marrow's large cells.57 The main reason for their existence is that they constitute the first stage necessary for blood coagulation and are exceedingly important for the closing of tears that occur hundreds of times a day in the blood vessels, and of which you are generally unaware.
After being released from the bone marrow into the bloodstream, thrombocytes tend to attach themselves somewhere. However, as evidence of the superior nature of their creation, thrombocytes do not adhere to the regular endothelial cells that line the blood vessels. Were they to do so, they would accumulate inside the vessels—clot, in other words—and lead to vein blockages. The blocking of just a single vein leading to the brain generally results in a stroke, or death.
These cells' adhesive properties emerge only when the endothelial tissue in a vein is damaged in some way. When the endothelial cells are harmed, the structural protein underneath them, known as collagen, is exposed. To the thrombocyte, the structure of collagen is very different from that of the cells lining these veins, and so their adhesive properties immediately come to the fore.
From 15 to 20 seconds after the opening of a wound, the clotting process begins. Thrombocytes arriving at this region deposit there the substances they contain, one of which is ADP, which causes a number of changes in the thrombocytes' characteristics. The thrombocytes begin to swell, assuming irregular forms. Numerous protrusions extend from their surface, which greatly increases their adhesive properties. This change taking place in the thrombocytes is a vital one, because the other thrombocyte cells, traveling haphazardly in the plasma, adhere to these thrombocytes that have undergone this alteration. The ADP deposited in the environment is the messenger that notifies the other thrombocytes of the situation.
This phenomenon takes place exceedingly rapidly. The wound inside the vein is shortly blocked up by means of this cooperation among thrombocytes, setting up the necessary condition for the subsequent process of blood coagulation. If the tear in the vein is a small one, then the thrombocyte plug alone is sufficient to halt the blood flow.58
The healing process goes further than this, however. The endothelial cells that make up the blood vessel walls release a protein, known as von Willebrand factor (VWF), that makes it easier for thrombocytes to adhere to the damaged vein wall, and also ensures that they perceive the trouble spot and do not pass by it. VWF first binds to the collagen in the damaged region, and the adhering of thrombocytes to the collagen also takes place in this way. It should therefore be claimed that the endothelial cells behave intelligently, recognize the structure of collagen, which is very different from their own, and make a conscious plan to assist the thrombocytes.
Yet these are only mere cells. They have no chemical knowledge or laboratories with which to produce a protein that will facilitate binding. They have no consciousness with which to identify damage, develop measures against it and thus preserve the body's life. These cells with their superior features—present and ready to serve the same purpose in every human being on Earth—cannot be the product of either human intelligence or an imaginary process of evolution. These can only be the work of God, Who endows all things with order, magnificence and flawlessness. God is He Who is sufficient to meet the needs of all things (Al-Kafi), Who surrounds them (Al-Muheet) and Who has the might to perform what He wishes, and when (Al-Qadeer). Only to Him are thanks given, and only He is the Praiseworthy (Al-Hameed).
He is the Innovative Creator (Al-Badee'). In the Qur'an this truth is stated thus:
The Originator of the heavens and Earth. When He decides on something, He just says to it, "Be!" and it is. (Surat al-Baqara: 117)
To return to the thrombocytes, these special cells perform a very important duty at the beginning of the blood coagulation process. Every element in this mechanism is of vital importance. It is impossible to do away with any one. For example, the absence of or deficiency in the protein VWF, which serves to facilitate thrombocyte binding, will spell the complete disruption of the blood clotting system. Defects in the clotting system cause serious diseases that can be treated only under special conditions, or sometimes not at all.
These miraculous entities possess very important features. These saviors, consisting of just single cells, contain within themselves special contractile proteins that permit expansion and contraction inside themselves, which proteins serve to make the blocking brought about by the thrombocytes even more powerful.59 Their duties do not come to an end with the initial clotting they set up. After the clot has formed completely, they continue their duties in different ways. This will be examined in more detail in the chapter on Blood Coagulation.
As the thrombocytes continue with this work, the body also takes a number of precautionary measures. Inside it, flat muscles in the walls of the damaged veins begin to contract, to reduce blood pressure and the amount of blood flowing to the region where the wound occurred. Thus while the thrombocytes are doing their jobs, any excess blood that might impair the clotting process is prevented from heading to the region, and the body will not lose too much blood.
These most rational measures are taken in even the smallest scratch in every vein in your body. You are probably unaware of this, however, and may pay no attention to any small scratch on your hand. Yet at that very moment, a great deal of activity is going on in that region. You do nothing about that tiny scratch, and you do not need to try and staunch the blood leaking from it. Indeed, you could not stop that flow even if you wanted to. Yet your cells with their perfect organization, charged with clotting the blood, take all the necessary precautions for you.
While all this is taking place, one danger arises that you may never have thought about. While thrombocytes adhere to one another and close up the wound, there's also the possibility of this clotting being carried outside the region in question and blocking a nearby vein just a millimeter or two in diameter. It is essential that this danger be averted at the wound site. Naturally, in this perfect system a precaution against this threat has also been taken. Against this danger, the arterial wall synthesizes a special compound, prostacyclin, which ensures that the thrombocyte plug forms only in the relevant place and halts once its job is done.60
Thrombocytes are merely cells. Their ability to never make a possibly deadly error is definitely not a property inherent in the cells themselves. It would be a violation of reason and logic to believe that they carried out all this coordination and organization of their own accord. The absolute existence and control of God can clearly be seen in this splendid order within our bodies. God is He Who creates all things flawlessly, the Almighty.