Early embryos

Confocal micrograph of mouse embryos at different stages during the process of dividing from the one-cell to the two-cell stage. The green fluorescence is staining the cytoskeleton that supports the structure of the cell and forms a 'spindle' during division of the cell's nucleus, while the red indicates chromatin within it, which contains the genetic information. The embryos each measure about 0.1 mm in diameter.

Dr Bernard Maro, Laboratoire de Physiologie du Developpement, Institut Jacques Monod, CNRS - Universite Paris VII.