Chapter 06. The Cell Membrane

1. Water	2. Lipid  Membrane
Figure 6.1 The phospholipid structure of the cell membrane, only one hundred-thousandth of a millimeter thick.

In the beginning, scientific circles considered the cell as the smallest living unit. But researchers have recently viewed the cell membrane, so much smaller than the cell in volume, as a new kind of living thing. This membrane that surrounds the cell displays features of a conscious living being, such as the ability to decide, remember, and evaluate. How does such a membrane only one hundred thousandth of a millimeter thick come to possess such features?

For your whole life, and at this very instant, 100 trillion of these membranes in your body make decisions and then act on those decisions without your even knowing it.

The cell membrane is an enclosure that determines the cell's boundaries, but its duty is not merely to surround and envelop it. The membrane also facilitates communication and interaction between neighboring cells and, probably most important of all, controls what goes into and out of the cell. So thin that it can be distinguished only with an electron microscope, its structure has been found to be made up of a double layer of lipids (fat) with proteins located on various sites within it (see Figure 6.1). It does not only display life, however. This membrane also has the extraordinary ability to make decisions and, due to its memory and the intelligence it displays, can be considered the brain of the cell.

This thin layer-made up of unconscious molecules such as fats and protein-carries out acts that we can consider intelligent.

To examine it in more detail, let's first look at the structure of the cell membrane that can carry out so many processes. The membrane is composed of a double layer of lipid molecules on both sides, facing inside and outside. Located within these lipid molecules are "gates" that facilitate entry into and exit from the cell, as well as receptors that let the membrane recognize its external environment. These gates and receptors, made from protein molecules, are located on the wall, where they control all of the entry and exit from the cell with the utmost care (see Figure 6.2).

Who is in Control?

A. Cell Surface B. Cytoplasm 1. Oligosaccharide group 2. Recognition protein 3. Channel protein	4. Transport protein 5. Electron-transport proteins 6. Receptor protein 7. Cholesterol 8. Phospholipid
Figure 6.2 Cell membrane of a pancreatic cell (right). In the above diagram, the mosaic model of this membrane is magnified.

The cell membrane's main duty is to envelop the organelles within it and hold them all together. But it also has a much more complex duty: From outside the cell, it procures the necessary molecules for the organelles to continue their functions, and for the cell to stay alive. Of all the numerous substances in the environment surrounding the cell, this membrane identifies the ones that the cell needs and allows only these inside. It is also very economical, never taking in more than the required amounts. And at the same time, it identifies and immediately removes harmful waste products within the cell. Another of the membrane's duties is to immediately communicate to the center of the cell messages sent via hormones from the brain and different organs of the body.

To be able to carry out all of these functions, the membrane must obviously be aware of all activity and developments within the cell, it must take stock of and control the necessary and extraneous substances within the cell. And it must possess a superior memory and decision-making ability.

What sort of "coincidence" could have brought about such an intelligent pile of lipid molecules?

Let us ask a further question, which by itself is enough to bring evolution to its knees. Is the so-called "intelligence" that carries out these processes a property of the membrane itself?

We are not talking about a computer or robot, but a thin layer of lipids with the occasional protein dispersed throughout, surrounding a cell. In this cell membrane is no thinking center or a brain that can carry out such complex processes. You will never find one, because as its name suggests, it is just a membrane.

Such superior features, in this structure with no ability to think, are displayed by God, Who presents another clear sign to prove His existence. In the face of all this evidence, those who reject Him are left with no excuse.

The Gates of the Cell

In the cell membrane are mechanisms that sometimes act like a gate, sometimes like a pump (see Figures 6.3, 6.4, 6.5, 6.6, and 6.7). These recognize substances that the cell needs, select them, and then bring them inside the cell, after expending a great deal of energy. This is not an event to be glossed over, because many miracles occur during this transfer process, many of whose mysteries have not yet been brought to light. In order for the cell to continue its existence, substances that need to get past the membrane include electrons, even photons, small molecules such as monatomic protons, ions, water, average-sized molecules like amino acids and sugars, and macro molecules such as proteins and DNA. Sometimes, with the help of many enzymes and with a huge amount of energy expended, a molecule much larger than the gate itself is taken into the cell. Sometimes the molecule to pass through the gate is so comparatively huge that the process can be compared to threading a rope through the eye of a needle. To facilitate the passing, the gap first widens, then returns to its original state. During this process, no harm comes to either the gate, the substance passing through, or to the cell.

1. External environment 2. Channel proteins 3.Transport proteins 4. Lipid layer 5. Electrochemical charges 6. Cytoplasm 7. Free diffusion 8. Diffusion via channels 9. Diffusion via transporters 10. Passive transport 11. ENERGY 12. Active transport

Figure 6.3 On the surface of the membrane, different gates allow different substances to be taken into the cell with the help of different enzymes. Generally, there are two types of protein gates: The first use energy for transport (active transport), selecting the necessary substances and transferring them in or out of the cell. The second type of gates are channel proteins that open at the right time to allow a particular substance to pass through freely. No energy is expended in this transfer. Some smaller molecules need no gate and they just pass freely through the membrane. This is called diffusion.

Figure 6.4 The working of the Sodium-Potassium (Na-K) pump. 1) The sodium ion settles in its own special gate within the cell. 2) ATP energy brings the pump to an active state. 3) The gate opens, and sodium ions are ejected outside the cell. 4) Potassium ion outside the cell settles in its gate. 5) The gate opens again with the energy provided by ATP. 6) Potassium is drawn into the cell.

	1. Closed 2. Open 3. External Environment 4. Gate	5. Cell membrane 6. Hydrophobic surface 7. Cytoplasm 8. Ion-selective filter
	Figure 6.5 The cell membrane channels, in their open and closed state. It is not known what decides whether these channels stay open or closed.

1. Outside The Cell 2. Solution 3. Channel Proteins 4. Outer Membrane 5. Space Between Two Membranes 6. The Periplasmic Substrate Binding Protein And The Solution It Binds To 7. Free Periplasmic Substrate Binding Protein 8. Transport Protein 9. Inner Membrane       Figure 6.6 In some cells, exchange of materials takes place in a number of stages. The diagram shows how a bacterial cell's double-layered membrane takes up a solution. The solution passing through the channel proteins in the first membrane is captured by a periplasmic substrate protein, found in the periplasmic space. The protein/solution complex attaches to a selectively permeable gate in the second membrane. Changes taking place in the protein's structure allow the solid substance to pass through the selective gate. With the energy acquired from a process known as ATP hydrolysis, the substance is taken into the cell.

1. Cytochrome 2. M protein 3. L protein 4. Lipid layer 5. Cytoplasm 6. H protein Figure 6.7 Protein gates within the cell membrane have a highly complex and superior structure. Different gates have different functions. This diagram shows the photosynthetic reaction center of a particular bacterium (Rhodopseudomonas viridis), made clearer with the help of X-rays. This gate's duty is to utilize light energy for the electron-transport reaction. It transfers an electron, using energy obtained from the sun in the form of photons, to the inside of the cell within a nanosecond (a billionth of a second). Once in the cell, the electron is captured by the electron-transport system and is made to take place in its reactions. The protein complex is formed from the coming together of four different proteins: (L, M, H and cytochrome). The dark regions in the upper part of the diagram represent the electron-carrying proteins. Such a highly developed mechanism for capturing just one electron for reaction in an area 250 millionths of a meter, and its taking place in a billionth of a second, are by themselves proofs of creation.

The Cell's Engulfing of Substances

The cell forms small vesicles that bud off from its own membrane and which carry out storage and transport processes. During the process of pinocytosis, a small portion of the cell membrane curls around towards the inside of the cell, taking in any nearby molecules from outside the cell. This portion of the membrane then pinches off, forming a vesicle that then enters the cell. In effect, the cell swallows the substances it needs (see Figures 6.8 and 6.9b).

In the process of exopinocytosis, the cell forms a vesicle within itself, around collected waste products. It then ejects this vesicle through the cell membrane, leaving substances carried by the vesicle outside the cell (see Figure 6.9a).

1. Pinocytosis 2. Nutrient	3. Lysosome 4. Lysosomes surrounding the vesicle	1. Exopinocytosis Figure 6.9 a) Substances are removed from the cell by the fusion of a vesicle formed within the cell with the cell membrane. b) Necessary substances are taken into the cell with the help of a vesicle formed from the cell membrane.
Figure 6.8 Pinocytosis seen in an amoeba, a single-celled organism. The substance taken inside is digested with lysosomes, which contain digestive enzymes.

Perfect Cooperation and Harmony

Trillions of cells in your body work together in amazing harmony. Your hair strands all grow at the same rate because the skin cells in your head cooperate with each other.

This sensitive relationship is carried out by special proteins and projections resembling hooks found within the cell membrane, which facilitate communication among different cells. These mechanisms start to form while you were still a fetus in your mother's womb. During cell division, some cells suddenly start to produce different proteins in a way not yet known. As a result of these different proteins, cells with structural differences start to appear. The cell membrane is also affected: Hook-like projections start to form on its outer surface and as a result, only cells of the same kind can come in contact with each other. In this way, billions of similar cells come together to form organs.

How and why did these hooks come about? This is another dead end for the theory of evolution because, as you can see once again, intelligent creation is at work here.

100 Trillion Organized Workers

Figure 6.10 Phagocytosis – a process in which macrophages reach out and swallow many bacteria.

Each of the 1,000 workers in a car factory must cooperate with discipline with all the others. Many control systems and a chain of command are set up to facilitate this organization. Each department produces the required parts: the motor parts are made in one area, the doors in another. Everybody knows which product is to be used where. Everything is under control.

But clearly, if 1,000 ignorant people who know nothing about making cars were placed in the same factory, and told to learn for themselves what to make and how, it would result in confusion and chaos.

In the human body, by contrast, there are not 1,000 but 100 trillion cells working together in complete harmony. This means that these cells are much more knowledgeable and educated than any factory workers. Not only are the processes carried out within these cells amazing, but the coordination amongst them is equally dazzling. They can recognize each other as a result of a system in their membranes, so that a stomach cell recognizes another stomach cell, and a hair cell recognizes a hair cell.

How do two membranes recognize each other? Who trained these workers? How do they manage to perform their duties with such fidelity?

Each of the 100 trillion cells does what the body expects of it. So how does each cell know what is required of it at each second? For example, the brain sends a command to divide the cells in a particular region. Special secretions called hormones help this take place, with each hormone going to the relevant cell to transmit the message from the brain. Once the "messenger" arrives at the cell, it transmits its command to receptor proteins located in the cell membrane, which then transmit the message they receive to the center of the cell, whereupon the cell goes into action accordingly.

Can we explain a cell's ability to understand a command given via an island of proteins located within a sea of lipids, and then transmit this to the cell center, and then, this cell's obeying this command and dedicating its life to producing a substance to be used in a place of which the cell has no knowledge? Of course not! Moreover, as we mentioned before, on the membrane there are hundreds of points of entry, receptors, and controllers, all aware of each other and working together in harmony.

But they are all simply unconscious protein molecules. Clearly, the cell membrane did not attain these qualities by itself. Somebody else has clearly created this system.

Figure 6.11 Macrophages (literally, "big eaters") are soldiers in the first rank of the body's defense system, swallowing and ingesting all manner of foreign agents found in the blood. Another of their duties is to alert T cells to help fight against enemies. The diagram on right shows a macrophage using its extensions to capture a bacterium. Above, a macrophage trying to engulf fat droplets that have entered the body.

Such a system has obviously been created for a purpose-for mankind to realize and more fully understand the existence of the One Who created them, God, Possessor of infinite mercy and compassion. Anyone of conscience and intelligence will see these signs and come to know God better. One verse expresses this attitude of the believers in the following way:

In the creation of the heavens and the Earth, and the alternation of night and day, there are signs for people with intelligence: those who remember God, standing, sitting and lying on their sides, and reflect on the creation of the heavens and the Earth: "Our Lord, You have not created this for nothing. Glory be to You! So safeguard us from the punishment of the Fire." (Qur'an, 3:190-191)

Raging War, Close Contact

There is a great war being waged by the human immune system, which cannot be seen with the naked eye. This battle continues day after day, every minute and in fact every second, between the cells protecting the body and the microbes and viruses entering from outside.

During the fiercest stage of the battle, when these two are in close contact, the membranes of some very special defense cells play an important role. These cells in the front line capture and then swallow all manner of foreign substances. They can do this because their cell membranes can identify any harmful substances entering the body. If need be, projections on the cell membrane extend out and capture bacteria and other microbes (See Figure 6.10). Once they have been captured, they're taken in by the membrane and swallowed by the cell. During this time of struggle, the cell membrane recognizes, captures and engulfs the enemy. The cell then digests it and uses the resulting substances in ways useful for the cell. Sometimes, special cells attach to a foreign substance and render it inactive, marking it for attack by fighter cells. Obviously, the stages of this war are not as simple as related here. At every stage, an organization is at work using such "intelligence" techniques as receiving, evaluating, and storing information.

This utterly complex war mechanism cannot be reproduced by even the latest human technology. It's been working for thousands of years and keeps doing so with the same perfection. In that case, what should we conclude? Is the cell membrane-a large part of which is made up of fatty molecules and which can hardly be seen with a microscope-more intelligent than man, who claims to be the most superior and intelligent of all creatures? Or has this membrane been inspired with a much more superior intelligence? This is the truth, and anyone who claims otherwise must accept that the cell's brain is superior to his own.

Some people attribute all of this to the brain, stating, "The brain sends the commands. The brain controls everything." With this conclusion, they think they have solved a great mystery with this simple logic. Comfortable with their answer for the time being, they feel no need to think about the rest. But their squashed conscience begins to feel a little uncomfortable. If they delve deeper, they know that they will be faced with questions they won't be able to answer: Doesn't the organ called the brain arise from the same cells? Do the commands given by the brain arise from decisions made by an assortment of microscopic fat and protein molecules? If so, which cells of the brain give these orders? Or do a certain portion come together to make decisions? How do these brainless, unconscious cells suddenly gain the ability to receive signals and give orders when they come together, and how do they act on these so perfectly?

Where is the brain that directs the amazingly coordinated division and differentiation of cells, when the human being is just a single cell and has no brain to speak of? The mother's brain? But her blood doesn't even mix with the baby's. What brain gives its orders to a test-tube baby, still a single cell fertilized externally, while it is beginning its development in a Petri dish?

Which brain controls a fertilized egg incubated by a mother hen until it becomes a tiny chick? Is there another secret brain that directs the single cell of the chick or human baby?

An unbeliever will face this type of questions when he starts to think more deeply. Eventually, he will have to accept these clear proofs of the existence of God and His superior creation-which is why he will continue to avoid thinking about the meaning behind these events from a wider perspective.

The logic of unbelief is a constant avoidance from meeting God, blinding oneself to everything that reminds one of Him and turns one to Him. Blinding oneself to the many proofs of His existence, and holding tightly to the slightest possibility assumed to somehow substitute for Him, this person has attributed his own creation, existence and the continuation of his life to trillions of cells, even to the molecules and atoms that compose these cells. In other words, he has chained himself to innumerable deities in the form of all these atoms and molecules.

A verse in the Qur'an informs us of the where and the why of the perfect coordination of these commands and their source which is nowhere to be seen:

It is God Who created the seven heavens and of the earth the same number, the Command descending down through all of them, so that you might know that God has power over all things and that God encompasses all things in His knowledge. (Qur'an, 65:12)

He is Lord of the heavens and the Earth and everything in between them, so worship Him and persevere in His worship. Do you know of any other with His Name? (Qur’an, 19:65)