nervous system

Introduction

nervous system, network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of the animal kingdom have at least a rudimentary nervous system. Invertebrate animals show varying degrees of complexity in their nervous systems, but it is in the vertebrate animals (phylum Chordata, subphylum Vertebrata) that the system reaches its greatest complexity.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

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