Charles Welsh began his Anatomy & Physiology teaching career upon graduating with a B.S. in Biology from the University of Pittsburgh in 1989. He entered graduate school in 1992 and continued teaching night classes. He accepted his first full-time teaching position at Clarion University of Pennsylvania in 1996. In 1997, he completed his Ph.D. in Comparative Anatomy, Evolutionary Biology, and Ornithology at the University of Pittsburgh. Teaching primarily in nursing and other allied health programs, he now brings his thirty years of classroom experience to the fifteenth edition of Hole’s Essentials of Human Anatomy & Physiology. At Duquesne University in Pittsburgh, Pennsylvania he received several teaching awards, as well as the Mentor of the Year Award for training graduate students to teach Anatomy & Physiology. Chuck and his wife, Lori, have three children and three grandchildren. They live in the historic town of Harmony, thirty miles north of Pittsburgh, with their youngest son, where they raise chickens and have a huge garden. Cynthia Prentice-Craver has been teaching human anatomy and physiology for over twenty-eight years at Chemeketa Community College. Cynthia’s teaching experience both in grades 6–12 and in college, her passion for curriculum development, and her appetite for learning fuel her desire to write. Her M.S. in Curriculum and Instruction, B.S. in Exercise Science, and extended graduate course-work in biological sciences have been instrumental in achieving effective results in the online and on campus courses she teaches. Cynthia was a contributing author for the Martin Laboratory Manual for Human Anatomy & Physiology, Third Edition, and Hole’s Essentials of Human Anatomy & Physiology, Fourteenth Edition. She co-authored Hole’s Human Anatomy & Physiology, Sixteenth Edition, and the Martin Laboratory Manual for Human Anatomy & Physiology, Fourth and Fifth Editions, and authored the digital content for these laboratory manuals. Cynthia is a member of the Human Anatomy and Physiology Society (HAPS) and the Textbook & Academic Authors Association (TAA). Her professional experiences include serving as a program chair for eight years, developing curriculum, serving on various committees, and being a reviewer and advisor of textbooks and digital products. Beyond her professional pursuits, Cynthia’s passions include reading and listening to books, attending exercise classes, walking outdoors, attending concerts, traveling, and spending time with her family and friends.

• 1 Introduction to Human Anatomy and Physiology2 Chemical Basis of Life3 Cells4 Cellular Metabolism5 Tissues6 Integumentary System7 Skeletal System8 Joints of the Skeletal System9 Muscular System10 Nervous System I: Basic Structure and Function11 Nervous System II: Divisions of the Nervous System12 Nervous System III: Senses13 Endocrine System14 Blood15 Cardiovascular System16 Lymphatic System and Immunity17 Digestive System18 Nutrition and Metabolism19 Respiratory System20 Urinary System21 Water, Electrolyte, and Acid-Base Balance22 Reproductive Systems23 Pregnancy, Growth, and Development24 Genetics and Genomics