This brief text consistently relates core course material to students' lives, clarifies the process of science and demonstrates how the theme of evolution integrates all of biology. Hailed for its clear writing, scientific accuracy, and real-world examples, Essential Biology is a brief non-majors biology text that focuses on the core concepts students need to make scientifically informed decisions throughout their lives. The book covers four major topics--cells, genetics, evolution/diversity, and ecology--and uses evolution as an overarching theme to tie all 20 chapters together. Human applications and the most up-to-date information on important issues show students how biology relates to their own lives. New Process of Science sections within the text draw students into the material and provide real-world examples of how the scientific method is applied. The Third Edition features dynamic new resources designed to focus students' study time and help them master the most challenging topics in the course. New state-of-the-art eTutor animations and audio MP3 Tutor Sessions guide students through the most challenging topics in biology.A customized Study Plan on the accompanying website pinpoints exactly where students have trouble, and directs them to relevant sections of the text and media for help.The Third Edition also includes the new Media Manager, which organizes all the instructor and student media in one convenient location, allowing instructors to easily and efficiently create engaging lectures. Three new types of assessment questions that test visual, quantitative, and critical-thinking skills offer new and creative ways to test student understanding.