The Blood’s Journey Through
The Veins

In previous chapters we referred to a gigantic network of nerves running right through our bodies. There is another such miraculous network. This consists of blood vessels. Like the network of nerves, blood vessels, too, circulate through the body. They are so long that their total length would be about 100,000 kilometres (62,000 miles) if they were spread over a flat surface. In fact, it is not hard at all to understand that there are blood vessels all around our body. Even a small scrape on any part of our body would start to bleed immediately. This proves that blood circulates all through our body. It is vital that we have blood vessels at every point because, as mentioned in the previous chapter, the nourishment required by the body cells is conveyed through the blood vessels. Oxygen that cells need for proper functioning is also carried to cells by the blood flowing through our veins.

Transportation of the nourishment in the blood vessels may be compared to transporting freight by ship. Prior to shipment, first of all goods are placed upon the ship at the port. Goods should be properly packaged and placed. After all are loaded, the ship sets out and heads for the port of its destination. When it arrives at the port, all packages are unloaded and distributed to the concerned sections. In the blood vessels, nourishment is similarly transported to cells, just as ships transport cargo across the ocean. Oxygen, fats and amino acids flow in the bloodstream in packages and are unloaded at the target cells. This transportation schedule never fails. Proper amounts of required substances are conveyed to relevant cells just on time. Otherwise, for instance, if a cell that needed oxygen received fats instead, this cell would die. It should be noted that even the slightest mistake in this system could result in serious harm. Such mistakes never happen except in unusual cases, however, because none of these came into existence by chance. Allah, the Creator, created this system perfectly for our service.

What is in The Blood?

As blood circulates all through the body, it fulfills many tasks. Now let's have a brief look at these tasks.

Transporting Cargo

We have already explained that all the kinds of substances that our body needs are conveyed to the concerned organs by blood. In the meantime, blood cells collect waste matters, like carbon dioxide, and make sure that they are discharged from the body. In a way, blood acts like a garbage grinder. Stopping by each of 100 trillion cells again and again throughout the day, it leaves the cells what they require and at the same time collect what is not needed.

There are different types of cells in the blood, each of which performs a different task. As seen in the picture above, some of these cells carry food while some others defend the body like soldiers.

Blood, which is merely a fluid, can faultlessly perform a task demanding such attention and responsibility. It knows each of the substances it carries, what it will be used for and to where it should be delivered. For instance, it does not mistakenly convey to a cell the carbon dioxide it has taken from another cell as a waste product. It always supplies cells with oxygen and removes carbon dioxide. Blood performs this task with no mistakes or fatigue, because it is a part of the perfect plan that Allah created in the human body. As they unconditionally surrender to the system created by our Lord, all blood cells perform their tasks without making any mistakes.

As seen in this picture, bacteria or microbes entering the body are seized , engulfed, and thus inactivated by warrior cells called macrophages. I. Macrophage, II. Bacteria, III. Blood cell, IV. Blood vessel

Soldiers in The Blood

Everyday our bodies struggle against many bacteria, viruses and microbes. Some are prevented from entering the body, while some manage to enter. But there are special defence cells in our bodies to fight against them that are called immune cells. These cells, which are like soldiers fighting against the enemy and protecting our bodies from dangers, move in the bloodstream. Whenever there is an enemy attack, they can reach the related part of the body through the blood vessels and easily fight against the enemy. Immune cells have not learnt their missions on their own. They have known them since they came into being. They start performing their duty and protecting the body the minute a baby born. This is an excellent detail in Allah's creation. Our Lord has taught cells which cannot be seen with the naked eye very important knowledge and placed them at our service.

Communication

Blood also serves as a means of communication in the body. There are messengers in the blood taking messages from one part of the body to another. These messengers, known as hormones, transport messages to the relevant organs like a postman delivering mails. Many significant processes, including the growth of the body, thirst, perspiration and control of blood sugar levels are thanks to such precisely delivered messages.

As seen in the picture above, hormones travel through the bloodstream with the messages they carry and deliver these messages to the relevant organs. I. Hormone receptor, II. Hormone, III. Cell membrane, IV. Blood capillary, V. Cell nucleus, VI. Hormone receptor, VII. Blood capillary, VIII. Hormone I. Macrophage, II. Bacteria, III. Blood cell, IV. Blood vessel

Blood That Heals Wounds

You must have observed that a slight skin wound stops bleeding spontaneously after a little while. This, in fact, is quite thought provoking since, under normal conditions, a liquid flowing from a hole cannot possibly stop flowing of its own accord.

To have a better understanding of this fact, suppose that you have a balloon filled with water. If you make a little hole in this balloon using a needle, water will leak out of the balloon. Will it stop leaking after a while with no intervention of yours? Of course not. All the water will keep leaking until the balloon runs out of water. This applies to all liquids in closed spaces.

Blood moves through a closed circuit of veins and leaks out in case of even a slight cut. However, it is of great importance for our health to stop its flow. You may have heard of people who die of excessive blood loss in accidents or operations. Well then, what causes blood to stop flowing a little while after a wound starts to bleed?

This is called blood clotting, which is one of the automatic security systems in our bodies. Some substances existing in the blood stop and close the wound. Thanks to the clotting ability of blood, excessive bleeding is prevented. As shown in the illustration on the right, some cells in the blood are informed of the damaged vein and head for that site at once. First they align themselves along the wound and obstruct the flow of blood by weaving a web. This web stiffens in time and forms what we call a scar.

Left: A CLOT FORMS Platelets release chemicals that make fibrin. The thread-like fibrin traps platelets and red blood cells (bottom). Aclot forms, which stops the bleeding. Center: BLOOD TO THE RESCUE Injured cells signal for help. Platelets stick together to plug the wound. Right: ATOUGH SCAB The fibrin, trapped cells, and fluid from the blood harden into a protective scab. Healing begins.

Now let's think together. Can this planned series of actions take place by chance? How is it that some blood cells are informed of damage somewhere in the blood vessels, which is like a gigantic world in relation to their size? Why do they strive to prevent the flow of blood? How do they know that they should close the wound in order to stop loss of blood? Who taught these cells that they should close the wound?

Blood leaks through the wound.. I. Red blood cell, II. Platelet, III. Damaged skin

Blood surrounding the wound coagulates.

Cells close up the wound like a plug. IV. Blood clot

A cut on your hand or a wound on your knee heals in a short time. The pictures below show some of what happens in your blood vessels during this healing process.

Cells could neither have learnt all these things by chance nor could they have accomplished them on their own. Even human beings, who have intelligence, cannot possibly originate such a detailed system and teach cells what to do. Certainly, the intelligence demonstrated by these cells does not belong to them. Allah inspires them and they act according to a perfect plan.

Allah informs us of the excellence in His creation as follows:

In the picture above, you can see the red blood cells stuck among the fibers of a blood clot. It is thanks to the clotting ability of blood that it stops flowing soon after you are injured.

A Miraculous Fluid with No Reproducible Equals: Blood Scientists have conducted many studies in order to produce a fluid similar to blood. However, having failed to do so, they gave up trying to imitate blood and focused on research in other fields. Scientists cannot imitate blood because blood samples withdrawn from a blood vessel clot at once and the structure of the blood becomes unfit for examination. It does not work to preserve the samples in glass test tubes either, because blood cells do not completely survive in tubes. Therefore, scientists had to separate cells in the blood and examine them individually. Undoubtedly, it is one of the most unreasonable and illogical explanations in the world to claim that such a perfect substance, which cannot even be imitated with all the information human beings have gathered for years, came into existence spontaneously and by chance. Allah created blood as a matchless substance. A blood cell that has many amazing abilities is merely one of the manifestations of Allah's infinite wisdom in the human body.

The Motor of The Body: The Heart

Have you ever thought how litres of blood circulate unceasingly through our body up and down? Every object needs a motor for continuous motion. Cars, aeroplanes, motorboats and even your remote-controlled toy cars move by means of motors. Likewise, blood circulating through our body needs a motor too. The motor that propels our blood night and day, for months and even for years is our heart.

Place your fingers on your wrist and wait for a while. You will feel the beating of your heart. Your heart beats 70 times in a minute, and pumps some 152 million litres (40 million gallons) of blood throughout your life. That much blood is an approximate equivalent of the amount 10,000 oil tankers will hold. These figures are astonishing, aren't they? Now suppose that you have to bail a cup of water from one bucket to the other, 70 times a minute. In the end your arm and hand muscles would ache and you would need to rest. However, your heart carries out this task all through out your life and it never takes any rest.

The Most Perfect Pump The most perfectly structured pump in the world is now beating on the left side of your chest. With its marvellous design and unceasing contractions, your heart makes the entire blood in your body complete 1,000 full cycles in a day. The heart is a pump made of flesh, which is approximately as big as one's fist. Nevertheless, it is clearly the strongest, the most durable and the most efficient engine in the world with respect to its capacity. We have many reasons to express the strength of the heart in this way. Most important, the heart uses a great deal of energy when it beats. With the energy used by the heart, blood can be raised up to 3 metres high. It may be helpful to give an example in order to make it easier to comprehend the heart's capacity. In an hour the heart can produce an amount of energy that is enough to lift an average car approximately one metre above the ground.
Your heart is an astonishingly strong muscle. It beats about 70 times in a minute, and pumps 59 cubic centimeters (3.6 cubic inches) of blood at each beat. A heart which beats 2,500,000 times in 70 years pumps some 152,000,000 liters (40 million gallons) of blood during this time. That much blood is the approximate equivalent of the amount pumped into the fuel tanks of 10 Boeing 747 jumbo jets every year.	The fuel tank of a jumbo jet will hold 217,000 liters (71,000 gallons) of fuel when full.

Original Pumps in the Heart

The heart, which is a muscular organ of about the size of one's fist, consists of two halves. There are two pumps in these sections. The left pump, which is stronger, drives oxygen-rich blood to all parts of the body. The right pump is weaker than the former and pumps oxygen-poor blood to the lungs. This transport from the heart to the lungs is over a short distance and is, therefore, called the "small circulation". The former is called the "large circulation".

Blood circulates through the entire body, from the brain to the lungs, thanks to the heart..
1-tissue cells 2-pulmonary artery 3-right atrium 4-left atrium 5-pulmonary vein	6-left ventricle 7-right ventricle 8-aorta 9-large circulation capillaries

Each of these halves of the heart is divided into two further sections. Blood between them passes to the other section through heart valves. These pumps operate unceasingly with a great amount of energy, thanks to which blood circulates through our bodies 1,000 times a day.

The Heart Maintains Itself

Machinery needs routine maintenance. It may be necessary to maintain some machine parts or to replace those that are worn out. Machines need to be treated with oil after a certain period of operation, so as to lessen wearing down by friction.
Like machinery, the heart, which keeps operating all the time, requires maintenance too. However, the heart carries out its maintenance itself; it lubricates itself.

How do you think a heart lubricates itself? The answer to this question is hidden in the creation of the heart. The outer surface of heart is covered by a sac consisting of two membranes. Between these membranes is a greasy fluid. This fluid acts like motor oil and facilitates easy operation of the heart. This self-protective structure in the heart reveals once again how perfect and complete is Allah's artistry in creation.