Donatella Paoli has been a researcher at the Sapienza University of Rome’s Department of Experimental Medicine Laboratory Semen-Sperm Bank since 1987, where she has been involved in research in the area of pathophysiology and immunopathology of reproduction, sperm, and molecular biology applied to male infertility. She is a lecturer in the graduate and postgraduate courses on Biotechnology of Human Reproduction, Clinical Pathology and Reproductive Medicine, and is also a tutor in the Master’s course on Andrology. She has presented papers and reports at a number of scientific conferences and has published articles and abstracts in medical journals, textbooks and proceedings of national and international conferences in the areas of Andrology, Pathophysiology of Reproduction.  Francesco Lombardo has taught Semen Examination at the Postgraduate School of Endocrinology since 1996. He has been a Professor of Endocrinology and Associate Professor of Applied Medical Sciences since 2007, and also teaches Medicine of Reproduction at the Faculty of Medicine and Dentistry at Sapienza University of Rome. Prof. Lombardo is the author or co-author of more than 200 papers in international and national Journals.Andrea Lenzi is a Full Professor of Endocrinology and directs the section on Medical Physiopathology and Endocrinology at the Department of Experimental Medicine, Sapienza University of Rome. He is Director of the Unit of Andrology, Reproductive Physiopathology, and Endocrine Diagnosis and Coordinator of Laboratories of Endocrinology at the Policlinico Umberto I University Hospital, Rome and is President of the Italian National University Council and Director of the Interuniversity Research Centre for Experimental Andrology (CASPER). Since 2016, he has been President of the National Committee for Biosafety, Biotechnology and Life Sciences, of the Council of Ministers and of the National Committee of Guarantors for Research at MIUR. From 2007 to 2017 he was President of the National University Council - CUN, an elected body representing the national university system, of which he has been a member since 1997. He has served as Secretary General of the International Society for Immunology of Reproduction (1999-2004), the Alps-Adria Society for Immunology of Reproduction (1998-2001), and the Executive Council of the European Academy of Andrology (2002-2010). Dr. Lenzi has also been President of the Italian Society of Andrology and Medical Sexology (2008-2010). He is a member of the editorial boards of several international scientific journals and has published more than 600 papers, review and chapters in national and international journals, books and proceedings.

• Introduction.- Notes on human spermatogenesis.- Morphological structure of the spermatozoon.- Non-sperm cellular components of the seminal fluid.- Morphological study of the seminal fluid.- Chromatin structure of the spermatozoon.