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and information from one side of the membrane barrier to the other. Which brings us back to the pimentos in our bread, butter, and olive sandwich. Many channel proteins are shaped like a tightly wound sphere, resembling the pimento-stuffed olives in our pictures. (See illustration.) When the electrical charge on the protein is altered, the protein changes shape, a change that creates an open channel running through the protein’s core. Channel proteins are actually two olives in one, depending on their electrical charge. In the active mode, their structure resembles a pimento-free olive, with an open gate. In their inactive mode the proteins’ shape resembles a pimento-stuffed olive that stays closed to the world outside the cell.

The activity of one specific channel type, sodium-potassium ATPase, merits special attention. Every cell has thousands of these channels built into the membrane. Collectively, their activity uses almost half of your body’s energy every day. This channel opens and closes so frequently that it resembles a revolving door in a department store on the day of a big sale. Every time this channel revolves, it shuttles three positive-charged sodium atoms out of the cytoplasm and simultaneously admits two positive-charged potassium atoms into the cytoplasm from the environment.

Sodium-potassium ATPase not only uses up a lot of energy, it also creates energy as surely as store-bought batteries provide energy for Game Boys (at least until your kids wear them out). Actually, the energy-producing activity of sodium-potassium ATPase is a lot better than the batteries your kids wear out because it turns the cell into a constantly recharging biological battery.

Here’s how sodium-potassium ATPase manages that trick. Every revolution of sodium-potassium ATPase throws more positive charges out than it lets in to the cell, and there are thousands of these proteins in each cell. As these proteins go through hundreds of cycles per second, the inside of the cell becomes negatively charged while the outside of the cell becomes positively charged. The negative charge below the membrane is referred to as the membrane potential. Of course the lipid, i.e., the butter portion of the membrane, does not let charged atoms cross the barrier, so the internal charge stays negative. The positive charge outside the cell and the negative charge inside make the cell essentially a self-charging battery whose energy is used to empower biological processes.

Another variety of effector proteins, cytoskeletal proteins, regulates the shape and motility of cells. A third variety, called enzymes, breaks down or synthesizes molecules, which is why enzymes are sold in your local health food store as a digestive aid. When activated, all forms of effector proteins, including channels, cytoskeletal and enzyme proteins or their byproducts, can also serve as signals that activate genes. These IMPs or their byproducts provide signals that control the binding of the chromosome’s regulatory proteins that form a “sleeve” around the DNA. In contrast to conventional wisdom, genes do not control their own activity. Instead it is the membrane’s effector proteins, operating in response to environmental signals picked up by the membrane’s receptors, which control the “reading” of genes so that worn-out proteins can be replaced or new proteins can be created.

How the Brain Works

Once I understood how IMPs worked, I had to conclude that the cell’s operations are primarily molded by its interaction with the environment, not by its genetic code. There is no doubt that the DNA blueprints stored in the nucleus are remarkable molecules, which have been accumulated over three billion years of evolution. But as remarkable as these DNA blueprints are, they do not “control” the operations of the cell. Logically, genes cannot preprogram a cell or organism’s life because cell survival depends on the ability to dynamically adjust to an ever-changing environment.

The membrane’s function of interacting “intelligently” with the environment to produce behavior makes it the