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 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:

Identify the spinal cord, cerebral lobes, and other brain areas on a diagram of the brain
Describe the basic functions of the spinal cord, cerebral lobes, and other brain areas

Explore our ability to sense the environment through our body. [7:43]

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