This document discusses the centrosome and centrioles. It notes that the centrosome is the microtubule organizing center of eukaryotic cells, composed of two centrioles arranged perpendicular to each other surrounded by pericentriolar material. Each centriole contains nine triplet microtubules in a cartwheel structure and proteins like centrin, nexin, and tektin. The centrosome functions to form the mitotic spindle during cell division and organize microtubules. It duplicates during S phase and the mother and daughter centrioles migrate to opposite poles during mitosis to form the mitotic spindle between them.

1. CENTROSOME & CENTRIOLES
Presented by :- SAKEEL AHMED
NIPERA1820PC01
Dept. of Pharmacology and Toxicology .
NIPER Ahmedabad
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2. INTRODUCTION
 The centrosome is the microtubule
organising centre (MTOC) of eukaryotic
cells.
 The centrosome was discovered by
Edouard Von Beneden in 1883 and later
described and named in 1888 by theodor
boveri .
 Centrosome composed of two centrioles
arranged at right angle to each other and
surrouded by an amorphous mass of
protein called pericentriolar material 2

3.  Each centriole of the centrosome is
based on a nine triplet microtubule
assembled in cartwheel structure and
contain
Centrin (Duplication)
Nexin
Tektin ( cilia & flagella)
 A triplet contains one complete and two
incomplete microtubules.
STRUCTURE
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5. FUNCTIONS
 Mitotic spindle formation during mitosis.
 Mother centriole makes cilia and flagella.
 Organise the Microtubules.
 Cell division :-
 Centrosome replicates during the S
phase of the cell cycle.
 During mitosis centrosome migrates to
opposites poles of the cell.
 Mitosis spindle then form between the
two centrosomes .
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6. Centrosome cycle
 Centrosome duplication :- G1 and S
phase
 Centrosome maturation :- G2 phase
 Centrosome sepration :- Mitosis phase
 Centrosome disorientation :- late
mitosis phase
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8. References
 Kumar Pranav , Life sciences
fundamental and practice 1 , 6th
edition 2018 , published by Pathfinder
Publication New Delhi .
 Paul T. Conduit and others ,
centrosome function and assembly in
animal cells, published by Nature
Reviews (Molecular cell biology) ,
2015.
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9. THANK YOU
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