2.4: Looking Back - Natural Systems
Assess your understanding of concepts related to this section by answering the questions below before proceeding with this chapter.
List the three basic elements of a system.
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(1) a functioning set of components, (2) a flow of energy which powers them, and (3) a process for the internal regulation of their functioning called feedback.
Define open and closed systems. Give an example of each from the Earth system.
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Open systems allow energy and mass across their system boundary. The various "spheres" of the earth system like the biosphere are examples of open systems. Closed systems allow energy but not mass to cross their system boundary. The earth system as a whole is an example of a closed system.
Explain the difference between positive and negative feedback.
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Positive feedback encourages system change towards a new state. Negative feedback reverses the direction of system change to return to it's original state.
Define system equilibrium.
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System equilibrium is a state when the inputs and outputs of a system are in balance.
Define exogenic and endogenic sources of energy.
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Exogenic source of energy comes from outside the earth system, notably solar radiation. An endogenic source is found within the earth system, notably the heat generated from the earth's core.