Introduction
Welcome to your new biology book! Let us try to explain why we believe you’ve made the right choice. This probably isn’t your first rodeo with either a textbook or other kind of guide to a school subject. You’ve probably had your fill of books asking you to memorize lots of terms (such is school). This book isn’t going to do that—although you’re welcome to memorize anything you take an interest in. You may also have found that a lot of books jump the gun and make a lot of promises about all the things you’ll be able to accomplish by the time you reach the end of a given chapter. In the process, those books can make you feel as though you missed out on the building blocks that you actually need to master those goals.
With Must Know High School Biology, we’ve taken a different approach. When you start a new chapter, right off the bat you will immediately see one or more must know ideas. These are the essential concepts behind what you are going to study, and they will form the foundation of what you will learn throughout the chapter. With these must know ideas, you will have what you need to hold it together as you study, and they will be your guide as you make your way through each chapter.
To build on this foundation, you will find easy-to-follow discussions of the topic at hand, accompanied by comprehensive examples that show you how to apply what you’re learning to solving typical biology questions. Each chapter ends with review questions—more than 300 throughout the book—designed to instill confidence as you practice your new skills.
This book has other features that will help you on this biology journey of yours. It has a number of “sidebars” that will both help provide information or just serve as a quick break from your studies. The 
sidebars (“by the way”) point out important information as well as tell you what to be careful about, biology-wise. Every once in a while, an 
sidebar (“in real life”) will tell you what you’re studying has to do with the real world; other IRLs may just be interesting factoids.
In addition, this book is accompanied by a flashcard app that will give you the ability to test yourself at any time. The app includes more than 100 “flashcards” with a review question on one side and the answer on the other. You can either work through the flashcards by themselves or use them alongside the book. To find out where to get the app and how to use it, go to the next section, The Flashcard App.
Before you get started, though, let me introduce you to your guide throughout this book. Kellie—I mean Dr. Cox—has taught biology for more than 20 years and also teaches AP Biology. We hadn’t had a chance to work with her before, but it’s been a pleasure to see how enthusiastic she is about her subject as well as how adept she is at explaining complex subjects. I don’t know whether she’d consider herself an artist, but we thought her sketches were so terrific we decided to leave them in, as we’re confident they will help you picture some of the trickier topics.
Dr. Cox has a clear idea what you should get out of a biology course and has developed strategies to help you get there. She has seen the kinds of pitfalls that students get into, and she is experienced at solving those difficulties. In this book, she applies that experience both to showing you the most effective way to learn a given concept—as well as advising you how to extricate yourself from traps you may have fallen into. She will be a trustworthy guide as you expand your biology knowledge and develop new skills.
Good luck with your studies!
The Editors at McGraw-Hill