Temporal Coordination of Physiologic Function
This extract was created in the absence of an abstract.
Excerpt
I. TIMING
A. Circadian Synchronization—with Phase Differences
The organism, as well as its parts, usually does not function at a constant rate along a 24-hour scale; many of its diverse, discrete changes do not recur at purely chance intervals. More often than might be expected from classical physiologic knowledge, we encounter circadian (circa, dies; [1–3]) repetitive sequences of events; this organization in time has apparently evolved through genetic adaptation of body metabolism to a terrestrial environment (for references see [1]).
An organism's circadian behavior seems to be plastic, rather than rigid; it involves the recurrence of like events in sequences that are not random and at intervals that are similar—rather than the repetition of identical changes after precisely fixed periods.
The circadian time structure, an adaptive feature of most species, is an aspect of functional integration in a given individual; its general characteristic resembles synchronization in the physical sense, i.e.,...
