Chapter 15 Nervous System Organization and Biological Clocks


The Organization and Evolution of Nervous Systems

  • Nervous systems consist of neurons organized into functional circuits
  • Many types of animals have evolved complex nervous systems
  • BOX 15.1 Genomics and the Evolution of Nervous Systems

The Vertebrate Nervous System: A Guide to the General Organizational Features of Nervous Systems

  • Nervous systems have central and peripheral divisions
  • The central nervous system controls physiology and behavior
  • Five principles of functional organization apply to all mammalian and most vertebrate brains
  • BOX 15.2 Functional Magnetic Resonance Imaging, Scott A. Huettel
  • The peripheral nervous system has somatic and autonomic divisions that control different parts of the body
  • The autonomic nervous system has three divisions

Biological Clocks

  • Organisms have endogenous rhythms
  • BOX 15.3 Sleep, David S. Garbe
  • Biological clocks generate endogenous rhythms
  • Control by biological clocks has adaptive advantages
  • Endogenous clocks correlate with natural history and compensate for temperature
  • Clock mechanisms are based on rhythms of gene expression
  • The loci of biological clock functions vary among animals
  • Circannual and circatidal clocks: Some endogenous clocks time annual or tidal rhythms
  • Interval, or “hourglass,” timers can time shorter intervals