THE NUCLEOLUS - A STRUCTURAL AND FUNCTIONAL INTERPRETATION

This review addresses the problem of understanding nucleolar morphology in terms of nucleolar function. Nucleolar morphology and function are outlined to serve as a basis for reviewing in situ-cytochemical results that have, so far, not led to a generally accepted view on the structure-function correlation for nucleoli. Nucleoli in meiotic cells are dealt with in detail, because they illustrate the relationship between chromosomes and nucleoli particularly well. Spontaneous and induced changes in nucleolar morphology are presented and an attempt is made to explain particular morphologies in terms of functional states. The use of nucleolar morphology as a tool in diagnostics is critically evaluated.