Centriolen en Centrosomen

Centrioles are barrel-shaped structures located near the nucleus.

Each centriole is composed of nine sets of triplet microtubules. It is about 0.5 micrometers long and 0.2 micrometers in diameter.

In animal cells, two centrioles are positioned at a right angle and linked by interconnecting fibers.

The centrosome, the principal microtubule-organizing center in animal cells, is made of two interconnected centrioles and a surrounding protein mass called the pericentriolar material.

The centrosome replicates before cell division and forms the two poles of the mitotic spindle. During anaphase- the fourth phase of mitosis, the spindle fibers originating from the centrosome participate in chromatid separation.

As a part of the cytoskeleton, the centrosome also regulates the movement and position of the nucleus and other subcellular organelles.

Centrioles have additional roles in some cells, including acting as the basal bodies for specialized structures such as cilia  and flagella which aid cell motility.