In cell biology, the centrosome is an organelle that is the main place where cell microtubules get organised. They occur only in animal cells.Also, it regulates the cell division cycle, the stages which lead up to cell division.nterestingly, centrosomes are not required for the progression of mitosis. When the centrosomes are irradiated by a laser, mitosis proceeds with a normal spindle. In the absence of the centrosome, the microtubules of the spindle are focused by motors allowing the formation of a bipolar spindle.