Clinical Notes
The Visible Human Project p. 7
Homeostasis and Disease p. 13
An Introduction to Studying the Human Body
This textbook will serve as an introduction to the inner workings of your body, providing information about both its structure and its function. Many of the students who use this book are preparing for careers in health-related fields—but regardless of your career choice, you will find the information within these pages relevant to your future. You do, after all, live in a human body! Being human, you most likely have a seemingly insatiable curiosity—and few subjects arouse so much curiosity as our own bodies. The study of anatomy and physiology will provide answers to many questions regarding the functioning of your body in both health and disease.
Although we will be focusing on the human body, the principles we will learn apply to other living things as well. Our world contains an enormous diversity of living organisms that vary widely in appearance and lifestyle. One aim of biology—the science of life—is to discover the unity and the patterns that underlie this diversity, and thereby shed light on what we have in common with other living things.
Animals can be classified according to their shared characteristics, and birds, fish, and humans are members of a group called the vertebrates, characterized by a segmented vertebral column. The shared characteristics and organizational patterns provide useful clues about how these animals have evolved over time. Many of the complex structures and functions of the human body discussed in this text have distant evolutionary origins. When we compare the particular adaptations of human beings with those of other creatures, we find two important principles: there are obvious structural and functional similarities among vertebrates, and form follows function.
This chapter explores the structural and