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 four major types of lipids
Explain the role of fats in storing energy
Differentiate between saturated and unsaturated fatty acids
Describe phospholipids and their role in cells
Define the basic structure of a steroid and some steroid functions
Explain how cholesterol helps maintain the plasma membrane's fluid nature

This pathway provides an overview of the four classes of biological molecules (lipids, carbohydrages, proteins and nucleotides) and how they are assembled.

This pathway provides an introduction to cellular mechanisms of transport, including a comparison of passive and active mechanisms. For a deeper look at this topic, we recommend the pathway Structure and Function of Plasma Membranes from the OpenStax textbook Biology for AP® Courses.

This overview of lipids explores triglycerides, saturated and unsaturated fat, steroids, waxes, and the role of lipids in energy.

About 48 million people (1 in 6 Americans) get sick, 128,000 are hospitalized, and 3,000 die each year from foodborne diseases, according to recent data from the Centers for Disease Control and Prevention. Microbes in food are the culprits. The purpose of these protocols is to investigate the effectiveness of bio-based cleaners at reducing bacterial counts on lab stations. This unit features 4 lessons and 10 files. Lessons are aligned to NGSS.

This pathway provides an overview of biological macromolecules and their properties. The resources in this pathway can be used to introduce or review the structure and function of lipids, carbohydrates, proteins, and nucleic acids. For a deeper look at this topic, we recommend the pathway Biological Macromolecules from the OpenStax textbook Biology for AP® Courses.