See how dietary fat from food we eat travels through the digestive system, and gets packaged and stored in the human body. [2:07]

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

Explore and review the biological molecules necessary for life.

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Here you can learn about biochemistry, the chemistry of the living world. Content explores carbohydrates, lipids, amino acid structure and proteins, enzymes, nucleic acids, and metabolism.

Trans fat is out, so back to the drawing board. In this unit, students will explore the chemical behavior of molecules related to the structure by 1) examining how the structure of high-oleic oil changes its performance characteristics, 2) learning methods of representing the structure of a molecule, 3) exploring research on high-oleic oil and 4) conducting a study of their own to compare high-oleic oil to regular refined soybean oil sold to consumers for cooking purposes. This unit features 3 lessons and 13 files. Lessons are aligned to NGSS.

Current trends in consumer behavior show that people want to eat healthier and are looking for simple ways to transform their diets. High oleic soybean oil features lower saturated fat while maintaining 0 grams of trans fat, which may lower cholesterol and support heart health. This unit features 2 lessons and 6 files. Lessons are aligned to NGSS.

Soybeans contain several components which innovators and entrepreneurs find valuable when creating greener products. What are the chemical building blocks in a soybean? This unit features 4 lessons and 6 files. Lessons are aligned to NGSS.

This video segment adapted from NOVA illustrates why carbon is at the center of life on Earth. It also asks whether carbon-based life might exist on other planets. [1:38]

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.

Find out what the human body needs to function at its best, and why.

All cells, organs and tissues of a living organism are built of molecules. Some of them are small, made from only a few atoms. There is, however, a special class of molecules that make up and play critical roles in living cells. These molecules can consist of many thousands to millions of atoms. They are referred to as macromolecules (or large biomolecules).