Superimposed images of chromosomes, microtubules, and the nuclear envelope. Optical sections 
of embryos triply stained for these entities were obtained at 0.2-^im focus intervals. Selected 
optical sections are displayed, each separated by 1 nm along the focus direction from the interior 
(lower left) to the surface ( upper right) of the embryo. Chromosomes, microtubules, and nuclear 
envelope are displayed in blue, green, and red, respectively. 
Research offohn W. Sedat, David A. Agard, and Yashui Hiraoka. 
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