Fluorescence Microscope Simulation of the Mitotic Spindle February 1, 2009 The mitotic spindle model (Yeh et al., 2008). (a) Side-on view; (b) end-on view. Helices represent the chromatin labeled with green fluorescing protein. Experimental and noise-free simulated images in side-on orientation (c-d) and end-on orientation (e-f). Differences in background between experimental and simulated images are caused by external chromatin not accounted for in the model. Structural variation in real specimens account for shape discrepancies.