Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.

By the end of this section, you will be able to do the following:

Describe the role of different glands in the endocrine system
Explain how the different glands work together to maintain homeostasis

This lesson will introduce the systematic classification of matter used in chemistry, defining the terms heterogeneous, homogeneous, pure substance, mixture, compound, element and providing examples.

Students experience firsthand one of the most common water treatment types in the industry today, flocculants. They learn how the amount of suspended solids in water is measured using the basic properties of matter and light. In addition, they learn about the types of solids that can be found in water and the reasons that some are easier to remove than others. Encompassing the concepts of force and motion, attraction and repulsion of charged particles, and properties of matter, during the associated activity students see scientific concepts they already understand through the eyes of engineers who apply them to the removal of solids from water via chemical flocculants.

What's in macaroni salad? Break down the pasta, mayonnaise, vinegar, mustard, vegetables, etc., and you're left with a bunch of molecules. Josh Kurz uses a delicious recipe to exemplify three types of mixtures (solution, colloid and suspension), while reminding us that we're all made of the same stuff. [3:57]

Learn about the classification of matter based on whether the chemical composition is pure or a mixture. Understand the definitions of elements, compounds, substances, and mixtures, and what the differences are between them. Five types of mixtures are explained, and the symbols used to represent elements in chemical formulae.