Homeostasis refers to any process, such as negative feedback, that living things employ to maintain stable conditions ind

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问题            Homeostasis refers to any process, such as negative feedback, that living
       things employ to maintain stable conditions indispensable for survival, and
       which arises from balances between forces and factors mutually influencing each
Line    other. Disturbance, or departure from equilibrium is of more consequence than
(5)     negative feedback: systems cannot correct themselves without straying. A car
       and its driver, for instance, can be regarded as a homeostatic system seeking to
       keep the car moving on track. Thus, if the car skids, the driver automatically
       responds by quickly steering the wheel in the opposite direction, but such
       abrupt negative feedback usually overcorrects. Likewise, if the magnitude of
(10)    correction is commensurate with the disturbance that triggered it, the
       correction may become an impressed change in the direction opposite to that of
       the original disturbance. Each feedback is of lesser magnitude than the last, so
       that as the oscillations of the system dampen, negative feedback achieves its
       goal in both artificial and natural systems.
The primary purpose of the passage is to

选项 A、describe in detail how the principles of homeostasis apply to living things
B、propose a modification in the most widely accepted theory of homeostasis
C、compare and contrast the role of positive and negative feedback in maintaining various applied systems
D、discuss the concept of homeostasis in the abstract and relate some of its most important principles
E、provide examples of systems which are ruled by the principle of homeostasis

答案D

解析
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