A Not so "Simple Cell"

...the phylogenetic tree is built on the premise that life evolved from a simple cell, but that "simple cell" has yet to be found. Would Darwin have ever even formulated his theory if he had possessed an electron microscope and been aware of the complexity and design of cells too small to be seen by the naked eye?

E. coli is placed on the lowest branch of the tree, assumed to be early in terms of evolution. Invisible to the naked eye, measuring 2 micrometers long and 0.8 micrometers in diameter, it is a marvelous example of design and complexity.

The cell is enclosed within a double wall, or membrane. Within this membrane are about 2,400,000 proteins, 1,800 kinds of molecules, 14,000 messenger RNAs. Add to that 22,000,000 lipid molecules and 280,000,000 small metabolites. All these jostle together in the cytoplasm which is 75 percent water, but they all have a purpose and work harmoniously...

A similar coordination is present in the tiny bacterium. All the proteins and molecules share in its internal metabolism. Their work is encoded in its genes. It is estimated that those instructions equal about ten pages in the Encyclopedia Britannica.

Metabolism requires energy, and energy in E. coli is provided by electrical power generated by the cell. An alternative energy source is also available, if required. Electricity drives its external flagella, which rotate like propellers. The "propeller shaft" penetrates through the membrane and into the cytosol by means of a bushing and can propel the little bug at a speed of about ten to twenty cell lengths per second.

Besides this, the direction in which the cell is driven is "computerized." The flagella all rotate together in a counterclockwise direction when the cell is in forward gear, but when its "computerized" sensing mechanism informs it that the gradient to which it is heading has changed, a "switch" is thrown, and the flagella change gears and begin a clockwise rotation. This results in what is called a "tumbling motion," and the cell changes direction.

Of course, I am writing metaphorically. The pictures elicited may be unreal, but the facts are correct. Such is just a brief introduction to this simple cell! (Lyndon K. McDowell, The Choice: Assumption or Assurance? Ministry, 2/2005, p. 17).