multicellular organism

life-form
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

multicellular organism, an organism composed of many cells, which are to varying degrees integrated and independent. The development of multicellular organisms is accompanied by cellular specialization and division of labour; cells become efficient in one process and are dependent upon other cells for the necessities of life.

Specialization in single-celled organisms exists at the subcellular level; i.e., the basic functions that are divided among the cells, tissues, and organs of the multicellular organism are collected within one cell. Unicellular organisms are sometimes grouped together and classified as the kingdom Protista. See protist.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Adam Augustyn.