Question

what is primary fibres and secondary fibres in centrosome plz explain with figure

Answer 1

As far as I know, the only fibers associated withe the centrosome are microtubules. Centrosomes are also known as MTOCs (microtubule organizing centers). They contain gamma-tubulin, which combines with the pericentriolar (spelling?) proteins to make gamma-TuRCs. This acts as a scaffolding allowing the alpha and beta tubulin to polymerize into the dimer that forms the microtubules. The gamma-TuRCs also cap the (-) end of the microtubule, preventing catastrophe and allowing polymerization at the (+) end, thus growing microtubules.

The only thing i can think of that makes sense is that the question is referring to the different types of tubulin.