Centriole
A
centriole in
biology is a hollow cylindrical
organelle found in most animal
cells, and cells of
fungi and
algae. The walls of centrioles are composed of nine triplets of
microtubules, each arranged at a right angle (so when looking down the tube, one end of the triplet pair points slightly out and the other end points slightly inwards). In cells, they are usually found in pairs at a right-angle to each other, forming a
centrosome. Centrioles are important in the
cell division process, organising the
spindle upon which the
chromosomes are pulled apart. Some animal cells may be able to separate without centrioles.