Biology Reference
In-Depth Information
Fig. 5.26 Sperm centrosome inheritance. The centriole (a-e, left) and aster (a-h, right)is
inherited at fertilization, duplicated and moves to either pole of a bipolar spindle to establish the
first mitotic spindle, at syngamy (bipolarization). Note sperm tail attached to centrosome. The
diagrams also show sperm incorporation, bipronuclear association, and nuclear disorganization,
2nd polar body extrusion at fertilization and the first cleavage. Sathananthan et al. (
1996
) TEM;
Courtesy Simerly et al. (
1995
)FM
Fig. 5.27 Abnormal multinucleated IVF embryos A. One-cell (fragmented) B. two-cell
(micronucleated) and C,D. three-cell embryos (multinucleated). Such defects reflect chromo-
somal
aberrations
that
could
be
caused
by
centrosomal
dysfunction.
x6,000,
x4,000
5.12 Centrosomes and Cancer
Boveri predicted the possible role of the centrosome in cancer (Munne
2006
) based
on his studies on abnormal early development in the sea urchin following dis-
permic fertilization, where he proposed an explanation for the origin of aneuploidy
in
cancer
through
asymmetric
mitoses
and/or
multipolar mitoses
due
to an
