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:

Discuss why every cell does not express all of its genes all of the time
Describe how prokaryotic gene regulation occurs at the transcriptional level
Discuss how eukaryotic gene regulation occurs at the epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels

This pathway includes an introduction to the ways that gene expression is regulated in both prokaryotes and eukaryotes. For a deeper look at this topic, we recommend the pathway Gene Regulation from the OpenStax textbook Biology for AP® Courses.

Videos, interactive activities, and articles explaining the influences that cause parts of the genome to be turned on and off. Learn how nutrition, behavior, stress and other factors determine gene expression.