Human Biology: Concepts and Current Issues, Global Edition

Book Preface

Should childhood vaccinations be mandatory for school attendance? Are genetically modified organisms (GMOs) a good or a bad thing? How will our future be affected by global warming and global climate change, and what, if anything, should we be doing about these phenomena? Are organic foods better for you than conventional foods? Questions such as these seem to come up almost daily. Those of us who find these questions and the news stories about them fascinating—and yes, even exciting!—have an obligation to help others understand science and the impact it has on their lives. Science is too much fun and far too important to be left to scientists.

New to This Edition

Changes to this edition are designed to encourage students who do not have a strong background in science to become actively engaged in the course. Improved pedagogy helps students focus their learning, directs their attention to key concepts and current issues in biology, and encourages thoughtful analysis and critical thinking.
●● New organization to the chapter opening material. To help the student develop an organized approach to a chapter’s content, each chapter opener now includes an outline of the main headings and a list of the key concepts to be covered.
●● Addition of a “connections” passage. The initial section of text in each chapter includes a “connections” passage, delineated by a chain-link icon , that provides the student with a sense of how a chapter’s specific topic interrelates to the overall subject of human biology, biology in general, and the larger world.
●● New ways to access MJ’s BlogInFocus entries. To rouse students’ interest in the science they encounter in their everyday lives, once again incorporated into each chapter are references to the author’s blog. With this edition, the MJ’s BlogInFocus is more accessible, as students can now view the blog entries via three different ways: directly with their smartphones by scanning a QR code, online by typing a URL into a search engine, or by visiting the MasteringBiology Web site. Each chapter includes two to four MJ’s BlogInFocus references. It is hoped that these references to the author’s Web site will encourage students to further explore science related topics that are of particular interest to them.
●● Refreshed Visual Content. To revitalize the visual content, 120 new photos replace images from the previous edition, and 16 figures are new. More than 30 other figures have been improved from the previous edition.
●● The use of numbered steps. Where complex processes are described, numbered step icons, 1 , 2 , 3 , and so forth, are included both in the text and in the accompanying figure. These correlating step icons will help students follow the logical sequence of events as those events unfold within a complex process.
●● Updated Features, Graphs, Tables, and Text. Key features of this text are currency and accuracy. Timedependent data has been updated with the latest information available. The updated text includes eleven new or extensively updated Current Issue features, three new Health & Wellness features, and more than 60 new MJ’s BlogInFocus entries.

The Focus Is On the Student

This book is written for students who do not yet have a strong background in science so that they, too, might share in the joy and wonder of science. Every effort is made to make the book accurate and up to date while keeping it inviting, accessible, and easy to read. The look and feel of the text is intentionally like that of a news magazine, peppered with short features likely to be of interest to the student and designed with a strong visual appeal. Each chapter begins with an outline of the main topic headings and a list of key concepts to be covered. Next, a Current Issue feature highlights a recent controversy or ethical/social/political issue related to topics to be covered in the chapter. In the introductory section of each chapter, a new “connections” passage helps the student understand just how the topic of the chapter fits into the bigger picture of human biology and the larger world.

Students are naturally curious about how their own bodies work and human diseases and disorders. We capitalize on this curiosity with Health & Wellness features that highlight timely health topics. In addition, organ system chapters generally conclude with a section covering the more common human diseases and disorders.

Once again, a key feature of the book is MJ’s BlogInFocus, brief references to a blog Web site written by Dr. Johnson in support of this text. The URL is www.humanbiologyblog. blogspot.com. Two to four MJ’s BlogInFocus entries per chapter highlight recent discoveries or news items relevant to the subject of each chapter. Most of the blog entries have an additional embedded URL that takes the student directly to a news source or research paper. We hope that MJ’s BlogInFocus entries and the author’s blog will encourage curious students to dig a little deeper into topics that interest them. New to this edition are the means by which students can access the blog entries. Students can now get to the blog in any one of three ways: They can scan a QR code, type a URL into a search engine, or visit Pearson’s MasteringBiology Web site.

To help students assess whether or not they understand the material, check questions throughout the text allow the students to test their understanding as they go along. Finally, at the end of each chapter is a range of question types, from concept review to recall to application, each designed to test the student’s knowledge of facts as well as stimulate their critical thinking skills.

Unifying Themes Tie the Subjects Together
Several unifying themes in biology hold the chapters together. Homeostasis, the state of dynamic equilibrium in which the internal environment of an organism is maintained fairly constant, is one of those recurrent themes. The concept of homeostasis ties in with another recurrent theme: Structure and function are related. Structure/function relationships are the very core of the study of anatomy and physiology, and both of these fields in turn rely on the most unifying concept in all of biology: evolution. Only in the context of evolution can anatomy and physiology be fully understood; without the concept of evolution, very little in biology makes sense. A predominant theme of this book is that each of us has choices to make—choices that will affect ourselves, other humans, and the entire planet. Should all children
be vaccinated against childhood diseases? Should we spend time and money preparing for a pandemic that may never occur? Will we be willing and able to slow the rate of global warming? Is it important that we save other species from extinction, and if so, how should we go about it? Students are encouraged to formulate their own views on these and other topics so that they will feel comfortable with related choices they make.

BRIEF CONTENTS
1 Human Biology, Science, and Society 31
2 The Chemistry of Living Things 51
3 Structure and Function of Cells 77
4 From Cells to Organ Systems 107
5 The Skeletal System 129
6 The Muscular System 149
7 Blood 169
8 Heart and Blood Vessels 189
9 The Immune System and Mechanisms of Defense 217
10 The Respiratory System: Exchange of Gases 249
11 The Nervous System: Integration and Control 273
12 Sensory Mechanisms 304
13 The Endocrine System 328
14 The Digestive System and Nutrition 352
15 The Urinary System 381
16 Reproductive Systems 403
17 Cell Reproduction and Differentiation 429
18 Cancer: Uncontrolled Cell Division and Differentiation 449
19 Genetics and Inheritance 471
20 DNA Technology and Genetic Engineering 493
21 Development, Maturation, Aging, and Death 509
22 Evolution and the Origins of Life 533
23 Ecosystems and Populations 551
24 Human Impacts, Biodiversity, and Environmental Issues 571