A Welcome Introduction to Science Dan Chiras once again offers a refreshing and student-friendly introduction to the structure, function, health, and homeostasis of the human body in a modernized ninth edition of Human Biology. This acclaimed text explores life from a variety of levels and perspectives, including cellular/molecular, by body system, through disease, and within the environment. Dr. Chiras retains the theme of homeostasis in this edition, emphasizing the importance of maintaining health by understanding the delicate internal balances of the body's systems within the context of the external environment. The Ninth Edition features a new chapter dedicated to the integumentary system as well as new sections covering evolution, injuries and diseases of the muscles, the pineal gland, and more. New information on GMOs, immunotherapy, vertigo, brain diseases, new cancer treatments, and more thought-provoking discussions encourage students to think critically about timely and relevant information that affects their lives. The logical organization, relatable topics, and outstanding pedagogical features, make Human Biology, Ninth Edition a fun and engaging learning experience.