13. Describe the structure of the following with the help of labelled diagrams.
(ii) Centrosome
Centrosome: The structure of centrosome is made up of two cylindrical structures called centrioles. These centrioles show a cartwheel-like organisation and both lie perpendicular to each other. A centriole is made up of microtubule triplets that are evenly spaced in a ring The adjacent triplets are linked together. A proteinaceous hub is present in the central part of a centriole. The hub is attached to triplets using radial spokes. Centrioles help in the organisation of spindle fibres. It also forms the basal body of cilia and flagella.