cephalization

cephalization
/sef'euh leuh zay"sheuhn/, n. Zool.
a tendency in the development of animals to localization of important organs or parts in or near the head.
[1860-65; CEPHAL- + -IZATION]

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      the differentiation of the anterior (front) end of an organism into a definite head. Considered an evolutionary advance, cephalization is accompanied by a concentration of nervous tissue (cephalic ganglion or brain) and feeding mechanisms in the head region that serves to integrate the activities of the nervous system. Some groups of organisms show full cephalization, but because their bodies are not divided into distinct trunks and heads, they cannot be said to possess a distinct anatomical head.

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Universalium. 2010.

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  • Cephalization — is considered an evolutionary trend,[1] whereby nervous tissue, over many generations, becomes concentrated toward one end of an organism. This process eventually produces a head region with sensory organs.[2] Cephalization is intrinsically… …   Wikipedia

  • Cephalization — Ceph a*li*za tion, n. Domination of the head in animal life as expressed in the physical structure; localization of important organs or parts in or near the head, in animal development. Dana. [1913 Webster] …   The Collaborative International Dictionary of English

  • cephalization — 1864, coined by U.S. zoologist James D. Dana (1813 1895) from Gk. kephale head on model of specialization, etc …   Etymology dictionary

  • cephalization — (Amer.) n. (Zoology) tendency in the animal kingdom of vital organs to be located in or near the head (also cephalisation) …   English contemporary dictionary

  • cephalization — [sef΄ə li zā′shən] n. [ CEPHAL(O) + IZATION] the tendency in the evolution of animal life for sensory organs, the nervous system, etc. to become centralized in or near the head …   English World dictionary

  • cephalization — ˌsefələ̇ˈzāshən, ˌlīˈz noun ( s) Etymology: cephal + ize + ation 1. : specialization of the anterior part of the animal body resulting in localization and concentration of sensory and neural organs in an anterior head 2. : the tendency to… …   Useful english dictionary

  • cephalization — noun Date: 1864 a tendency in the evolution of organisms to concentrate the sensory and neural organs in an anterior head …   New Collegiate Dictionary

  • cephalization — n. [Gr. kephale, head] The process by which the highest degree of specialization became localized in the anterior end, or in the head, in animal development …   Dictionary of invertebrate zoology

  • cephalization — noun An evolutionary trend in which the neural and sense organs become centralized at one end (the head) of an animal See Also: telencephalization …   Wiktionary

  • cephalization — 1. Evolutionary tendency for important functions of the nervous system to move forward in the brain. 2. Initiation and concentration of the growth tendency at the anterior end of the embryo. * * * ceph·a·li·za·tion or Brit ceph·a·li·sa·tion .sef… …   Medical dictionary

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