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Centriole

Centriole
Introduction
Animal cell and the cells of some microorganisms and lower plants contain two centrioles located near the exterior surface of the nucleus and absent in higher plants.They are usually placed at right angle to each other.
Structure
In cross-section, each centriole consists of a cylindrical array of 9 microtubules. Each of the 9 microtubules is further composed of three tubules.
Function
Centrioles are involved in cell division. Just before cell divides, its centrioles duplicate and one pair migrates to the opposite side of the nucleus. The spindle then forms between them.

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