Developmental Aspects of the Cell Cycle discusses the molecular, organelle, cellular, and organismal levels of cell cycle, cell proliferation, and cell differentiation. It addresses the possible antagonism between the ability of cells to proliferate and to differentiate. After brief historical, theoretical, and methodological background information for each cell system, this book concentrates on the mechanisms involved in the regulation of cell proliferation and differentiation. The book presents systems in which mass cultures of cells can be induced to undergo a synchronous transition from one cell state to another, enabling the amplification of cellular and biochemical events to be analyzed with the available morphological and biochemical techniques. Some chapters explain the possibility of cell state production by a microenvironment that occurs at the organismal level, in which a series of mitotic and growth steps causes cells proliferation. The concluding chapters discuss cell proliferation and differentiation in specific cell system, such as embryonic chick and male germ cell. This book will appeal to investigators in many disciplines, teachers, and life sciences students, particularly, to molecular, cellular, and developmental biologists.