Return to Menu Centriole structure Like Cilia and Flagella, Centrioles are also made of microtubules. The difference is that they contain 9 sets of triplets and no doublet in the center. How the triplets in the basal body turn into the cilium doublet remains a mystery. Centrioles come in pairs, each organized at right angles to the other. This figure shows an electron micrograph of a pair of centrioles and the cartoon compares the cross section of a cilium with that of a centriole.
Centrioles organize the spindle apparatus on which the chromosomes move during mitosis.
You will learn more about that in the lectures designed to cover this phenomenon. Return to Menu Centriole Replication. Centrioles replicate autonomously like mitochondria and peroxisomes. Each grows out a single microtubule from which the triplet can form. Once a centriole is made, daughter centrioles can grow out from the tubules at right angles as shown in this cartoon.