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 relationship of amplitude and frequency of a sound wave to attributes of sound
Trace the path of sound through the auditory system to the site of transduction of sound
Identify the structures of the vestibular system that respond to gravity

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

Identify the general and special senses in humans
Describe three important steps in sensory perception
Explain the concept of just-noticeable difference in sensory perception

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

Describe four important mechanoreceptors in human skin
Describe the topographical distribution of somatosensory receptors between glabrous and hairy skin
Explain why the perception of pain is subjective

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

Explain in what way smell and taste stimuli differ from other sensory stimuli
Identify the five primary tastes that can be distinguished by humans
Explain in anatomical terms why a dog’s sense of smell is more acute than a human’s

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

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

This template course was developed from generally available open educational resources (OER) in use at multiple institutions, drawing mostly from a primary work published by OpenStax College Concepts of Biology, but also including additional open works from various sources as noted in attributions on each page of materials.