Part II has been reorganized; Chapter 5 Cardiovascular System: Heart and Blood Vessels now precedes the other human body systems, signifying its importance to homeostasis. Chapter 6 Cardiovascular System: Blood has a change of title and organization to emphasize that blood is a part of the cardiovascular system.

A new chapter, Chapter 20 Genetic Counseling, has been added to Part VI and includes medical information regarding chromosomes, genes, and DNA. This timely chapter serves as the pinnacle of the student's study of genetics, because it demonstrates the relevancy of genetics to his/her life.

Part VIII has been reorganized into three chapters. Chapter 27 Human Population, Planetary Resources, and Conservation combines Chapters 26 and 27 from the eighth edition and shows the relationship between consumption of resources and pollution and their effects on biodiversity.

The Human Systems Work Together illustrations have been extensively revised. The number of illustrations has been reduced to five to keep the illustrations interesting and instructive, and the print has been enlarged to more clearly emphasize the key points of homeostasis. These new illustrations face narrative in the chapter entitled Homeostasis. This narrative has been rewritten to peak student interest by relating the material to an everyday event. Together, the illustration and narrative provide excellent tools for students to understand the important concept of homeostasis.

The set of questions provided at the end of each chapter in Human Biology has been expanded to include critical-thinking questions. These questions are directly related to the vignette that appears at the beginning of the chapter, encouraging students to apply the concepts they just learned to the life situation presented in the vignette. Answers to the questions are provided in the Appendix of the book.

Many chapter-opening vignettes and boxed readings have been rewritten to increase student appeal.

For example, Bioethical Focus readings describe ethical situations, and many timely topics have been chosen, including, Stem Cell Research, Bans on Smoking, and DNA Fingerprinting and the Criminal Justice System. Questions to guide class discussions are also included as part of the box.

The Looking at Both Sides feature that was previously part of the Bioethical Focus readings has been moved to the end-of-chapter material. The placement of this material allows instructors to direct students to the book’s Online Learning Center (www.mhhe.com/maderhuman9) after a chapter has been studied. There, students will find many activities to enhance their learning, including activities that require students to read opposing viewpoints, think critically about both sides, and form an opinion.

New designs for the part openers, chapter openers, and readings give the book a fresh look.