International Review of Cytology presents current advances and comprehensive reviews in cell biology - both plant and animal. Authored by some of the foremost scientists in the field, each volume provides up-to-date information and directions for future research. Articles in this volume address endogenous ligands of PACAP, VIP receptors in the autocrine-paracrine regulation of the adrenal gland, ultrastructural dynamcs of human reproduction, from ovulation to fertilization and early embryo development, chromosomal variation in mammalian neuronal cells, automated interpretation of protein subcellular location patterns, cell and molecular biology of human lacrimal gland and nasolacrimal duct mucins.