Fig. 22. The sequence of events associated with the denucleation of the lens fiber. A. An elongated nucleus in the cell of a superficial bow fiber. B. The nucleus of a cell located deeper in the lens cortex. The nucleolus at this time appears more dense. C. As the fiber becomes more internalized, the nucleus rounds up, while the nuclear and cytoplasmic matrices become less distinguishable. The nucleolus, now very dense, displays a spokelike configuration. D. The nuclear envelope vesiculates as the nucleus breaks down. E. Remnants of some ribonucleoprotein material are the last remains of the nucleus. (Kuwabara T, Imaizumi M: Denucleation process of the lens. Invest Ophthalmol 13:973, 1974)