Control Structure
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Governance control appears as action initiation that proceeds downward through the hierarchy of living systems and their organization units, ending at the biomolecule level. There, as physical action takes place, it is aggregated upward through the hierarchy to finally produce higher-level action at the top. Separately, and starting at the bottom, sensors react to changes in the external and internal environments, which are aggregated upward and interpreted as results of the control actions.


Governance Interface with Organization Units
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Living system homeostatic control involves orchestrated interaction between a living system's governance mechanism, its organization units and components. In the diagram below, the red box represents a living system's governance mechanism. The blue box represents the rest of that living system, including its organizations, component living systems, and their lower-level internal structures.


The diagram in the red box shows the governance view of control. It includes a portion of the Scenario Control Unit diagram, which is extended here to show how governance interfaces with the rest of its living system. It portrays how governance sees only its initiation of the control command, and how it must wait for sensory feedback to determine the results of that command.
The diagram in the blue box shows the living system internal view of what happens after the control command is received from governance. It portrays the three phases that are required to respond to that control, each of which involves the living system's organization units, their component living systems, and their lower-level structures down to the biomolecule level.


Governance Commands
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Governance commands go from a higher-level living system to its lower-level living system components. These commands are issued whenever the higher-level living system needs to restore the homeostatic balance of its life functions, or to anticipate such an imbalance from interactions with its environment.
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A living system's governance commands are acted upon by selected component living systems in the form of specialized physical work. This directed work by the lower-level living systems carries out the necessary life function corrections of its higher-level living system. From the component's view, any actions taken to support its higher-level living system are "work." This is in contrast to actions taken by a component on its own behalf, which are viewed as "self-maintenance." See Roles and Constraints for details of this distinction.

When one of these control commands has been issued, a three-phase process is required to provide a response that is recognizable by the governance control mechanism. This is because the higher-level living system's governance cannot directly see the detailed physical action that takes place. It can only interpret resulting sensory patterns that indicate changes in the living system's external environment or internal conditions that may or may not satisfy the original need.
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Control Structure Chart
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Governance control commands can be independently initiated from superorganism, organism or cell levels. For completeness, the following chart portrays the overall control structure that is involved in the three-level living system's response to a superorganism's governance control command.
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Control Structure
Hierarchy Control Initiation Resulting Work Sensory Awareness
Superorganism
 organization
  Organism
   organ
    Cell
     organelle
      Biomolecule

Hierarchy shows the sequence of control and response levels, from superorganism to biomolecule. Note that living systems and their organization units are involved as separate control levels. When a control command is issued by a superorganism's governance mechanism, all lower-level living systems must collectively participate, even though some of their individual members may not be available.
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Control Initiation shows three steps that occur within each level of living system and organization unit as control initiation proceeds from superorganism downward through the hierarchy to the bottom biomolecule level. Between any two levels of the hierarchy there is a fan-out, where a single higher-level control initiation has been orchestrated into multiple control initiations that are assigned to designated units at the next lower level.
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Resulting Work shows three steps that occur within each living system and organization unit, as resulting action starts at the bottom biomolecule level and proceeds upward to the superorganism level. Between any two levels of the hierarchy there is a fan-in, where collective results of work at the lower-level are aggregated to produce a higher-level result.
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Sensory Awareness shows three steps that occur within each living system and organization unit, as awareness proceeds from bottom to top. At each level of the hierarchy there is a fan-in, where lower-level sensory inputs are aggregated into a higher-level sensory pattern.
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Specialization
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Specialization plays a key part in governance control. Throughout the control structure hierarchy, a myriad of different kinds of work is required. At all three living system levels, organization units and their components have been specifically configured and developed with capability to perform the prescribed kinds of work that are needed. Each control command results in an enormously complex sequence of highly-organized, controlled and specialized work actions, starting at the biomolecular level and proceeding up through the hierarchy. The Living Systems Model embodies an abstraction of the key features from this complexity, to provide a concise view of a living system's architectural structure.


Governance Control Sequence explains how work is initiated step-by-step down through the entire hierarchy of control levels.


©1995-2012 Ackley Associates   Last revised: 7/20/11
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