This book is a compilation of Human Physiology lecture notes meant specifically for undergraduate and postgraduate medical students as well as biomedical, nursing and other medical-related courses. The contributors of this book are the Universiti Sains Malaysia Physiology lecturers who have strived to present the information as accurately and effectively as possible. The contents are arranged according to body systems which comprise Cell and Tissue, Respiratory System, Cardiovascular System, Gastrointestinal System, Renal System, Nervous System, Endocrine System, Reproductive System and Musculoskeletal System.