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Is Complexity Plus Efficiency Evidence for Intelligent Design?

One Molecule at a Time

If you have ever taken a biology class or are a science program addict, you've probably heard of cellular respiration as part of the subject of metabolism.¹ Cellular respiration is the process in which nutrients acquired by the cell are broken down into the energy needed for survival. It's incredibly complex, yet efficient in its function and elegant in its delivery.

How does the cell do it? One molecule at a time.

Let's say you drink a 12 oz. can of cola. The average can contains about 40 grams of sugar. To understand what is happening in a tiny cell, we need to know the number of molecules of sugar, also known as sucrose, not the number of grams. Sucrose is actually glucose attached to another sugar, fructose. In the cell, an enzyme converts fructose to glucose so that it can go through the regular process. For the purpose of this discussion, we can estimate that every sucrose molecule will produce two molecules of glucose in the cell.

Cellular respiration breaks down glucose. So, approximately how many molecules of glucose can we get from a single can of cola? It turns out there are more than 100 sextillion molecules or, written out, there are 100,000,000,000,000,000,000,000 glucose molecules that can theoretically be obtained from a can of cola. This number is easily beyond comprehension and yet, the cells in our bodies are equipped to efficiently convert this glucose into useful energy.

Sugar Becomes Energy

Inside the cell, the process of respiration consists of three stages and will break down a molecule of glucose into carbon dioxide, water, and energy. The energy that is extracted from this molecule will be temporarily stored in another molecule called ATP, which will be used to fuel all the other processes going on in the cell like making proteins and DNA.

Now, the names of these stages aren't important and a detailed analysis of each step is beyond the scope of this article, but consider this: The end result of breaking down sugar into carbon dioxide, water and energy is no different that the end result of combustion. In other words, cellular respiration literally burns sugar up. But when we burn things, what usually happens to the energy that is produced? It is lost as heat, which is great if we are talking about burning wood in a fire to keep warm. The problem for the cell is that heat is a useless form of energy. It doesn't help the cell make proteins; in fact, enough heat will destroy them. So, the cell needs a way to capture the energy and temporarily store it. That's when ATP molecules come into play. They are stable, making them great places to store the energy that the cell needs to survive.

The cell then has an incredible task: break down a molecule of glucose into harmless by-products and minimize the amount of heat that is lost by capturing the energy in ATP. The way that the cell does this is a marvel.

In the first stage, energy must be invested in the first two steps. This means that ATP, which is being produced by this process, needs to be around from the beginning. In terms of the number of enzymes involved, it takes at least 24 enzymes (depending on the organism) to accomplish this task. The nature of these enzymes ranges from simple enzymes to complex assemblies of enzymes working together. The three stages occur in different parts of the cell, so the cell needs ways to transport things around much like a conveyer belt without the belt. On top of all this, there are various feedback loops set up, so that if things in the middle of the process slow down, then there are ways to communicate to the front of the line to speed things up. This pathway also helps slow things down to avoid any bottlenecks in the process.

Reaping What You Sow

So, what's it all worth? In the end, cellular respiration will break down one molecule of glucose and produce 36 molecules of ATP for energy storage. Add a ton of zeroes behind that to account for all the glucose that comes from a can of cola and suddenly "sugar rush" becomes a very accurate description.

Some of the energy that was in the glucose molecule is lost as heat. That is true of any process that converts fuel into energy, including the internal combustion engine found in cars. In fact, efficiency is a gauge of how well a machine converts fuel into useful energy rather than energy wasted as heat. When it comes to cars, fuel efficiency is obviously important in order to keep overall fuel costs low; however, the amount of heat generated is also important since heat wears down oil and engine parts.

A typical car has a fuel efficiency of around 30 percent for burning fuel into carbon dioxide, water and energy only (if the fuel burns cleanly, which doesn't always happen). The efficiency of cellular respiration for "burning" glucose is around 40 percent. Although these are approximations that depend on various factors, it is clear that a biological cell is more efficient than today's highly engineered automobile engines.

Ten percent may not seem like much of a difference, but consider the fact that the parts of the cell can change shape to a degree, are in motion, and are highly temperature sensitive because they are made of proteins and other carbon-based molecules that float around within an environment that is mostly water. On the other hand, the parts of a car engine don't change shape, contain few moving parts, and have high temperature resistance because they are mostly made out of metal such as aluminum or steel. If you consider these differences in addition to the number of cellular parts involved, the degree of complexity, and the feedback loops, cellular respiration is amazingly efficient.

Enhancing Efficiency

In 2005, the U.S. Department of Energy announced that it would be providing more funds to projects aimed at increasing the efficiency of passenger automobiles from 30 percent to 45 percent by 2012.² How will the scientists and engineers working on these projects accomplish this task? Efficiency can be improved by improving the design, which often involves seeking new methods or materials. In fact, one could argue that many of the improvements technology has provided have been focused on enhancing efficiency on larger scales or at faster speeds.

The bottom line is that humans cannot improve the efficiency of technology without improving the design.

Interpreting the Evidence

Biological cells, on the other hand, cannot improve their design on their own to make cellular respiration more efficient. One might even argue that cellular respiration cannot become any more efficient than it already is. However, Darwinian evolution argues that cellular respiration has been improved over time through natural selection and variation by mutations in the genetic code. If you think about evolutionary processes for a minute, you can get a sense of the incredible amount of inefficiency that would be present in having only the fittest of any population survive. Isn't that a process that wastes the "unfit"? Isn't that highly inefficient in itself?

This begs the question: Can a highly inefficient process produce a highly efficient design such as cellular respiration?

The answer is, yes. The development of the internal combustion engine for use in automobiles itself is an example of a highly inefficient process. Consider the amount of trial-and-error that went into creating it and the number of modifications that have been made and discarded. We drive around in cars today without an appreciation for the number of hours many incredibly intelligent scientists and engineers from all over the world spent working on this problem — producing failure after failure before making a significant contribution to improving the design.

Yet, as inefficient as this was, one can imagine an even more inefficient way to proceed; that is, allowing anyone to modify the design. If all people, educated or uneducated, were given materials and fuel and told to design a more efficient engine, there would be great amounts of waste. It is the fact that intelligence provides a natural screening process of good and bad ideas as well as the skill to implement an idea into reality that makes for a more efficient process.

Now, extend that to its logical extreme. What if an engine could be produced from a highly intelligent individual who understood all aspects of the problem? We would expect that that engine would be as efficient as physically possible.

Intelligent Design Weighs In

Isn't this what intelligent design proposes when it comes to highly efficient processes in nature like cellular respiration, the bacterial flagellum or DNA? Doesn't it seem reasonable that the highly efficient process of cellular respiration was designed by a highly intelligent individual who understands all aspects of the problem?

In the final analysis, the inefficiency of Darwinian evolution seems to be a poor explanation for the efficiency of many of the processes found in the cell. There may be cases in which efficiency can emerge from inefficiency, but not to the degree of complexity present in cellular respiration.

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Do you think the complexity of cellular respiration is a possible argument for intelligent design?

Join the discussion!

Considering that respiration is just one process going on in the midst of hundreds to keep a single cell alive, it is evident that both the complexity and efficiency of cellular processes are highly indicative of an intelligent designer.