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:

Explain how electromagnetic waves differ from sound waves
Trace the path of light through the eye to the point of the optic nerve
Explain tonic activity as it is manifested in photoreceptors in the retina

What's it like for people who are visually impaired? How does it happen and what can be done? Be sure to read the whole article and click on the tabs to the right for more information.

This tutorial looks at the anatomy of the eye and how the sense of sight works. This is the first part of a learning module. Subsequent sections cover how images are formed and detected, the concept of accommodation where the eye adjusts its focus, and how farsightedness and nearsightedness are corrected. Includes detailed calculations using physics formulas, e.g., to find the quantitative relationship between the object distance, image distance, and focal length.

Students learn about glaucoma its causes, how it affects individuals and how biomedical engineers can identify factors that trigger or cause this eye disease, specifically the increase of pressure in the eye. Students also learn how RFID technologies transfer energy through waves and how engineers apply their scientific understanding of waves, energy and sensors to develop devices that measure the pressure in the eyes of people with glaucoma. Students conclude by sketching their own designs for a pressure-measuring eye device, preparing them to conduct the associated activity in which they revise, prototype and evaluate their device designs made tangible with a 3D printer.

Students learn about the anatomical structure of the human eye and how humans see light, as well as some causes of color blindness. They conduct experiments as an example of research to gather information. During their investigations, they test other students' vision, gathering data and measurements about when objects appear blurry. These topics help students prepare to design solutions to an overarching engineering challenge question.