In my last article I noted that as a multicellular organism (MCO), your body consists of an intracellular and extracellular space. Both are made up mostly of water. 

By weight, water makes up about 60 percent of your body. Of this total, two-thirds is inside your cells, i.e., the intracellular fluid (ICF). And one-third is outside your cells, i.e., the extracellular fluid (ECF).

If there’s one thing everyone can agree on, it’s that, whether it’s unicellular or multicellular, life is impossible without water. As biologist Michael Denton wrote in his book The Wonder of Water:

There is almost universal agreement that a complex living system remotely comparable with cellular carbon-based life on Earth could only be instantiated in a liquid medium. Life requires a liquid matrix. And the optimal matrix is water, which just happens to be liquid in the temperature range required for the (meta)stability of organic compounds uniquely fit to serve as the building blocks of life. This is surely an arresting concurrence!

Not surprisingly, then, since mainstream science assumes the origin of terrestrial life — from random chemicals evolving into simple organisms, followed by the evolution of complex ones — took place by the unguided processes proposed by evolutionary biology, its search for extraterrestrial life involves finding water.    

Not So Fast!

To stay alive and work properly, an MCO’s cells must maintain control of their volume (ICF) and chemical content, and the MCO itself must maintain control of its ECF volume and chemical content. “Chemical content” means the concentration, i.e., the amount of a given chemical (like sodium or potassium) dissolved within a given volume of fluid, in this case the ICF or ECF. 

Think of chemical concentration and its relationship to volume as like the sweetness of your coffee or tea. The more sugar you put into a given volume, the higher the concentration and the sweeter it tastes. If it is too sweet, the only way to reduce the sweetness is to decrease the concentration of sugar by increasing the volume of coffee or tea by adding more to the cup. This is how chemical concentration and volume relate to each other, whether in your cup of coffee or tea, or the water in your body.

The same thing applies to the ICF and ECF. The space inside the cells and outside the cells must have the right volume and the right concentration of chemicals to live and work properly. 

In an MCO, the chemical content within its intracellular space is very different from what is in its extracellular space. This difference must be maintained for proper tissue and organ function, that is, for survival itself. 

In particular, the ICF has a high concentration of potassium ions (K⁺ ions) and protein, and a low concentration of sodium ions (Na⁺ ions). The ECF has a high concentration of Na⁺ ions and a low concentration of K⁺ ions and protein. Remember, the differences between the chemical content of the ICF and ECF must be maintained for survival. 

This means that the mere presence of liquid water (with various chemicals in solution), although necessary for life, is not, in and of itself, sufficient for life. To stay alive, you need the right amounts of water with the right chemical content in the right places, all the time. 

Life and Death

If cells (ICF) take in too much water they expand and die, literally, by explosion because of the physical limits of the surrounding cell membrane (like an over-inflated balloon or tire). If cells (ICF) don’t have enough water, the reduced volume and increased concentration of chemicals within them causes the metabolic processes to malfunction which results in cell death. 

If there is too much water outside the cells (ECF) then — as noted two articles ago in the case of my heart failure patient Joe — the build-up of fluid between the cells, particularly in the lungs, makes it harder to breathe. That causes a drop in oxygen and a rise in carbon dioxide, resulting in death.

If there isn’t enough water outside the cells (ECF), this reduces the blood volume and blood pressure which ultimately compromises blood flow to the tissues and organs, resulting in death.

The Laws and Forces of Nature

Without considering how the laws and forces of nature affect life, evolutionary biologists claim life came about through the unguided processes of natural selection acting on random variation, i.e., the laws and forces of nature, alone.

The laws and forces of nature affect the water and chemical content of the intracellular and extracellular spaces. In fact, when left to their own devices, rather than causing life, these laws and forces cause death by way of any one of the above-mentioned four mechanisms. 

In this and two subsequent articles, I will look at some of the innovations life has come up with to combat the laws and forces of nature so that MCOs can control the volume and chemical content of their ICF and ECF. 

Diffusion and Osmosis

When two solutions of the same solute (dissolved chemical) but of different concentration are placed on either side of a membrane, the laws of nature force them to become the same on either side. Two different mechanisms for this are diffusion and osmosis. 

Why is this important? The interface between the ICF and the ECF is the cell membrane. This means that the forces of diffusion and osmosis are always in play between the ICF and the ECF.    

Diffusion is a passive process of transport across a permeable membrane that allows both the solute and water to pass through. The solute moves from an area of higher concentration to an area of lower concentration until the concentration on both sides of the membrane is the same — the volume of water on either side does not change. 

The ICF has a high concentration of K⁺ ions and a low concentration of Na⁺ ions. The ECF has a high concentration of Na⁺ ions and a low concentration of K⁺ ions. Since the cell membrane is permeable to both Na⁺ and K⁺ ions, diffusion naturally forces K⁺ ions to move out of the cell into the ECF, while Na⁺ ions move from the ECF into the cell. 

The situation results in a hard problem. If the force of diffusion is not resisted and is allowed to continue to its natural end, the cell will lose control of its chemical content (the K⁺ ion concentration will decrease too much and the Na⁺ ion concentration will increase too much) resulting in cell death.    

Osmosis is a passive process of transport across a semi-permeable membrane in which water can pass through, but the solute can’t. Since the solute can’t move across the membrane, water, instead, moves from the area of lower concentration to the area of higher concentration until the concentration is equal on both sides. The volume of water increases on the side that had the higher solute concentration and decreases on the side that had the lower solute concentration. 

The ICF has a high concentration of protein. The ECF has a low concentration of protein. The cell membrane is semi-permeable, allowing water to pass through but not most proteins. As diffusion forces K⁺ ions and Na⁺ ions to pass through the cell membrane in opposite directions, the high concentration of protein in the cell makes water move from the ECF into the cell (ICF). 

This dynamic results in another hard problem. If the force of osmosis is not resisted and is allowed to continue to its natural end, the cell will lose control of its volume by letting water flood in and it will die, literally, by explosion because of the physical limits of the cell membrane

The Laws of Hard Problems

If not prevented, this double whammy of diffusion and osmosis will soon render the cell dysfunctional and it will die. What is a cell to do? 

Consider what one innovation (or more) would have to do to solve these two very serious problems. Here are the words of my co-author Steve Laufmann (an engineer) from our book, Your Designed Body. 

The dual realization that the problems are incredibly hard to solve, and the solutions must be complete (and coherent), pushes us into a corner. How can these two hurdles be overcome, and at the same time? One of us (Steve) formulated two laws of hard problems to encapsulate what will strike experienced engineers as unarguable truisms.

• Laufmann’s First Law of Hard Problems: No amount of wishful thinking will make a hard problem go away. No amount of magical thinking can ever solve a truly hard problem. Wishing it were solved cannot make it so. Sadly, this is always true, and all the more so with the tough problems the body faces in its struggle to be alive.
• Laufmann’s Second Law of Hard Problems: Hard problems require ingenious solutions. The mere presence of a problem does precisely nothing to make a suitable solution appear. This is because the problem itself is not a causal force. Solving problems takes a problem-solver — one with the requisite type of problem-solving skills. This is all the more so with life, where neither the problems nor the solutions are trivial.

It turns out that it took just one innovation — well, really, about a million of them strategically located inside the cell membrane of each of your cells — to prevent diffusion and osmosis from wreaking havoc. The problems weren’t trivial, and as you’ll soon see, neither was the ingenious solution.

Pumping for Life

Consider what you’d have to do if you owned a large boat that was constantly leaking in water. You’d have to constantly remove the water, otherwise your boat would sink. Can you think of a machine that large boats use to prevent this from happening? The answer is a pump!

This is precisely the type of molecular machine your cells have, which allows them to maintain control of their volume and chemical content. Just as water leaking into a boat can cause disaster, so too can K⁺ ions leaking out of, and Na⁺ ions and water leaking into, the cell. To address this, your cells have about a million sodium-potassium pumps in their cell membrane. 

Each pump is made up of an alpha subunit, consisting of about a thousand amino acids, and a beta subunit, consisting of about three hundred amino acids, all hooked together in a specific order. These pumps constantly push three Na⁺ ions out of the cell for every two K⁺ ions they bring in. (See the image at the top of this article.)

The sodium-potassium pump is the innovation that allows your cells to combat the forces of nature — like diffusion and osmosis — and in doing so, prevents disaster: cell and MCO death. The pumps’ constant action reverses the natural tendency for diffusion to try to force the fluid inside and outside the cell to have the same concentrations of Na⁺ and K⁺ions. In addition, by keeping Na⁺ ions from entering the cell, they prevent water from entering, too. 

In this way, the sodium-potassium pumps allow your cells to maintain their volume (ICF). In addition, by keeping Na⁺ ions and water out of the cells, they maintain the ECF. They are the main reason that the ICF has two-thirds and the ECF has one-third of the total body water.  And they are responsible for the physiological dictum that in your body, “water follows sodium.”

No Free Lunch

But there’s a price to be paid by your body for battling the forces of nature. The job of the sodium-potassium pumps is like walking against a hard-driving wind. Remember, they constantly push Na⁺ and K⁺ ions in a direction that is opposite to where diffusion is naturally forcing them to go. 

This effort, needed for survival, requires tremendous energy. At rest, about one-quarter to one-half of the total energy needs of your body are taken up by the millions of sodium-potassium pumps in each of your trillions of cells. 

My Experience as a Physician

As a hospice physician I can tell you that knowing how important the sodium-potassium pump is for cell survival explains a lot — especially about what causes death. 

At rest, your brain’s nerve cells (neurons) use up the most energy, dedicating 70 percent to their sodium-potassium pumps. This high amount of energy is needed, not only to maintain the volume and chemical content of the neurons, but also the resting membrane potential (the difference in voltage between the inside and outside of the neuron) without which they cannot function.

The final common pathway to death, no matter the cause, is usually cardiopulmonary arrest. This is when the heart stops, followed almost immediately by the breathing, or the breathing stops, followed soon after by the heart, or they both stop at the same time. When cardiopulmonary arrest occurs, the body is no longer able to bring in new supplies of oxygen, nor send it to the tissues. 

The brainstem — the part of the brain that makes you aware, controls your cardiovascular system, and tells you to breathe — consists of neurons, which have one of the highest rates of metabolism. Given the vital importance of the sodium-potassium pump, which cells in the body do you think will be the most susceptible to a lack of oxygen?  

Without new supplies of oxygen, within a few minutes of cardiopulmonary arrest, sodium-potassium pumps malfunction and the cells of the brainstem die. And so do you, because now your body can no longer tell itself to breathe. 

Evolutionary “Explanations”

Keep in mind what we’ve learned about the sodium-potassium pump and its components:

1. Alpha subunit = about one thousand amino acids.
2. Beta subunit = about three hundred amino acids.
3. About a million pumps located exactly where needed in the cell membrane of all your cells.
4. A pump controls chemical content by pumping out three Na⁺ ions for every two K⁺ ions it brings in.
5. It controls volume by keeping Na⁺ ions out of the cell, which helps keep water out, too.
6. At rest, this pumping accounts for one-quarter to one-half of your body’s total energy needs.
7. Pumping maintains the resting membrane potential of neurons without which they cannot work.

See what you think about these two “explanations” of the origin of the sodium-potassium pump. From Google AI:

The evolution of the sodium-potassium pump, is believed to have originated in prokaryotes, most likely within methanogenic Archaea, with the beta subunit appearing later with the emergence of Holozoa and the gamma subunit in early vertebrates.

From “Evolutionary history of Na,K-ATPases and their osmoregulatory role” in the journal Genetica:

The Na/K pump is a key enzyme to the homeostasis of osmotic pressure, cell volume, and the maintenance of electrochemical gradients. Its alpha subunit, which holds most of its functions, belongs to a large family of ATPases known as P-type, and to the subfamily IIC. In this study, we attempt to describe the evolutionary history of IIC ATPases by doing phylogenetic analysis with most of the currently available protein sequences (over 200) and pay special attention to the relationship between their diversity and their osmoregulatory role. We include proteins derived from many completed or ongoing genome projects, many of whose IIC ATPases have not been phylogenetically analyzed previously. We show that the most likely origin of IIC proteins is prokaryotic, and that many of them are present in non-metazoans, such as algae, protozoans or fungi.

Do you think these two “explanations” fulfill Laufmann’s first and second laws of hard problems? Notice that there is no mention of where the information came from to design and fabricate these pumps. There is no mention of where the information came from to place enough pumps exactly where needed. And there is no mention of where the information came from for the pump to perform its vital functions.  

Phylogenetic analysis, although important, is like comparing the blueprints for the engine and transmission from different vintages of cars. It doesn’t explain where the blueprint came from, or anything about the fabrication and interface of the engine and transmission with other parts, nor the capacity of either to allow the car to function properly.  

Similarly, describing the parts within an organism does not explain anything about its origin. As paleontologist Günter Bechly commented in one of his recent articles at Evolution News, “All those cleverly devised just-so stories turn out to be unsupported evolutionary fairy tales.” Any questions?

Next time we’ll look at an innovation in your body that allows it to have sufficient blood volume.