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 how signaling pathways direct protein expression, cellular metabolism, and cell growth
Identify the function of PKC in signal transduction pathways
Recognize the role of apoptosis in the development and maintenance of a healthy organism

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

Describe how cancer is caused by uncontrolled cell growth
Understand how proto-oncogenes are normal cell genes that, when mutated, become oncogenes
Describe how tumor suppressors function
Explain how mutant tumor suppressors cause cancer

This pathway provides an introduction to the cell cycle and how its regulation is important to normal cell division. Cancer is often caused by unregulated cell division. For a deeper look at this topic, we recommend the pathway Cell Reproduction from the OpenStax textbook Biology for AP® Courses.

This animation from NOVA: "Battle in the War on Cancer: Breast Cancer" describes how oncogenes cause cancer and how cancerous cells can spread throughout the body.