Also called the spindle apparatus, a body formed within
a cell at mitosis or meiosis,
which takes parts in the distribution of chromatids
to the two daughter cells. It is composed of a gel and is commonly but not
always ellipsoidal in shape. The spindle appears at metaphase,
and chromosomes become arranged at its
equator. It contains many microtubules,
some running from spindle-attachments, or centromeres
to one spindle pole, others from pole to pole. The microtubules are responsible
for movement apart of the chromatids during anaphase.
See mitotic spindle for more details.