Midichlorians....

If ever a word sent thrills down the spines of countless Star Wars fans in those heady days before The Phantom Menace was released, that was it. What could these mysterious things be, many wondered. Unfortunately, The Phantom Menace explained very little, and George Lucas himself revealed little more. What exactly are the facts?

There are a couple of incontrovertible statements. First of all, midichlorians are said to create life. They are symbiotic organisms, without which life could not exist. Additionally, the higher one's concentration of midichlorians, the more likely it is that one is Force sensitive, and the stronger the sensitivity.

But what are these fascinating organisms? Many people have compared them to mitochondria, including George Lucas, (if memory serves) which is a fairly good comparison, but not an exact one. So, really any discussion of midichlorians should first begin with an explanation of mitochondria.

The mitochondrion is the "warp core of the cell." In other words, it is the energy manufacturing unit present in all cells in the human body, and in every living eukaryotic cell. All cells have not just one mitochondria, but dozens. Some muscles cells have a very high mitochondrial density. More simplified cells, prokaryotic ones, such as extremely primitive bacteria do not possess mitochondria.

In fact, "the endosymbiosis theory," as I believe it is termed, states that it is likely that the mitochondria arose as result of the engulfment of a smaller prokaryotic cell by a larger one. The smaller cell took on the task of energy production in return for food and protection from the larger cell. There are a few lines of evidence for this theory.

First of all, there is the fact that DNA from the nucleus of one of our cells is in the form of a double helix. Bacterial DNA in contrast is circular. Interestingly enough, mitochondria have DNA distinct from nuclear DNA, and its form is circular. Additionally, mitochondria do not reproduce by means of the nucleus and ribosomes. Instead they reproduce via fission, just like bacteria. Lastly, no mitochondria are transmitted by the sperm cell from the father (they are present, but only the haploid DNA transmits from the sperm to the ovum). All mitochondria arise from those already present in the unfertilized ovum, again supporting the idea that the mitochondria have a symbiotic relationship with the cell. (As an interesting side point, studies of the mitochondria have lead back to a "mitochondrial Eve," or the first mother of us all.)

Going back to midichlorians, what are the differences? First, the fact is that mitochondria are found in the cell, not in the interstitial fluids, such as the blood. Secondly, mitochondria produce energy stored in ATP, between the second and third inorganic phosphate of that molecule. Midichlorians do not produce any energy, per se. Exactly how they work on a scientific basis has not been revealed. Of course, we can always guess, can't we? And the third point is that mitochondria are found in different concentrations throughout the human body. A muscle cell would have far more mitochondria in it than would a dermal cell. So, it is not quite possible to say what a person's "mitochondrial density is." In fact, it is possible, by means of exercise, to increase one's mitochondrial density in skeletal muscle cells. Such a fact has not been suggested nor supported in any way by either the films or the supporting materials.

Now that we know what mitochondria are and are not, how do they work? I'll address that next time.