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A cell is a supercomplex microscopic structure that performs thousands of reactions coordinated perfectly in space and time every moment, and from the perspective of physics, it is clearly an improbable construction. Nevertheless, it survives and perpetuates its structure via reproduction. Theoretically, there are two alternative ways that the living cell might accomplish this marvel of nature’s biotechnology; all these reactions are spontaneously coordinated, or, alternatively, the cell has evolved a control system to coordinate that myriad of chemical reactions within the cell.The first possibility, that thousands of spatiotemporally precisely coordinated biochemical reactions within the cell can spontaneously occur, seems next to impossible. Emergence is a descriptive term that does not explain or help us explain anything. The same can be said of self-regulation. Loose as they are, these terms only avoid the questions on how cell structures arise and are maintained.
The alternative explanation of the phenomenon is that the wonderful spatiotemporal coordination of many thousands of chemical reactions occurring in a cell, and many more in a multicellular organism, are controlled by a specialized system. Human experience shows that even the simplest artificial devices or machines cannot function without control systems involving continued human supervision and regulation of material and energetic supply or built-in control systems.
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An example of a simple, one-variable control system with a built-in controller is a thermostat used for regulating a room’s temperature. The control system consists of a thermostat and a furnace. The thermostat is the controller of the system; it receives information on the temperature of the room via a sensor (thermometer) and compares it to the desired temperature, a selected set point. When the temperature is lower than the set point, the thermostat switches on the circuit, which causes the furnace to produce heat. When the temperature exceeds the set point, the circuit opens, and the furnace switches off until the temperature falls below the set point again, and the cycle repeats. But if regulation of a single variable, room temperature, cannot be achieved without a control system, what should one think of incomparably complex systems such as living cells or multicellular organisms, which have to both control and regulate thousands of different variables, in differential patterns in tens or hundreds of different cell types? The control system is a sine qua non of the existence of
all living organisms. The emergence and evolution of living systems are inseparable from the evolution of the control system; the evolution of complex animal structures and functions is associated by a parallel increase in the complexity of the control systems.
If a control system with a controller is necessary for regulation of a single variable such as the temperature of a room, it is absolutely necessary to regulate hundreds and thousands of variables coordinated in time and the nanospaces of a cell. In multicellular animals, the development and maintenance of normal structure are a function of an integrated control system . It is a hierarchical system of controls on several levels of organization, in which higher levels of control impose restrictions on lower levels to minimize the noise in the transmission of information downward to the cell level, where gene expression is regulated and patterns of gene expression are determined.
The continued evolution of control systems increased the independence of living systems from their environment, and as a rule, the degree of complexity of a living system parallels the degree of the complexity and sophistication of the control system. More complex systems require more complex and sophisticated control systems. Recognition of the presence of a control system that is capable of maintaining the normal structure of the organism implies that it “knows” what the normal structure
is. But if it has information about its own structure, there is no reason to doubt that it is capable of transmitting it to its offspring
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