This is the structure which controls the entrances. It surrounds the cell, is made of lipids and certain proteins and acts as a barrier made to contain all of the cell’s activities within itself. It acts as a wall separating the internal and external environments. It contains a number of proteins called receptors which detect chemical signals present in the blood stream, transmitting coded messages to the cell and enabling it to react to environmental variations.
Having passed through the entrance, the molecule is immediately handled by specific proteins which execute the cell’s functions. These proteins are called “enzymes“. If necessary, the enzymes will immediately use the molecule; if it is not immediately needed it will be stored in the cell’s storage center, called the “Golgi apparatus“.
Bruce Lipton*, in his research, has in particular analyzed “the membrane’s intelligence“. He has demonstrated that a cell can survive without its genes for more than two months. When he removed nuclei from cells, he saw that they could sustain the coordinated operation of their physiological systems (respiration, digestion, excretion, motility, etc.). They could still communicate, protect themselves and grow appropriately, in response to the surrounding environment’s stimuli. The reason they end up dying is that without DNA they can neither replicate nor replace weakened proteins. According to Lipton, the membrane receives information from the environment, decides what may enter the intracellular space, and regulates internal cell functions. “Just like the nervous system, the cell membrane analyzes thousands of stimuli from the microenvironment”, (Lipton). This capacity for “intelligent” interaction with the environment is what makes the membrane the cell’s true brain. When the membrane is destroyed, the cell dies. Without the receptor or executive proteins embedded in the membrane, “they become comatose, similar to brain death.”