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 adaptive immunity
Compare and contrast adaptive and innate immunity
Describe cell-mediated immune response and humoral immune response
Describe immune tolerance

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

Explain cross-reactivity
Describe the structure and function of antibodies
Discuss antibody production

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

Describe hypersensitivity
Define autoimmunity

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

Describe physical and chemical immune barriers
Explain immediate and induced innate immune responses
Discuss natural killer cells
Describe major histocompatibility class I molecules
Summarize how the proteins in a complement system function to destroy extracellular pathogens

Describes how autoimmune diseases affect the body.

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This one-page study guide on immune system diseases covers key terminology and describes some common immunity disorders. It is available for download with free registration.

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This study guide on the immune system covers key terminology and the different lines of defense the human body has to protect itself against pathogens. It is available for download with free registration.

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Discusses immunity and the differences between active and passive immunity.

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Overview of immunodeficiency and causes of immunodeficiency.

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Dr. Stephen O'Brien of the National Cancer Institute discovers a 700-year-old mutation that makes a person resistant to HIV infection. From Evolution: "Evolutionary Arms Race."

Dr. Stephen O'Brien of the National Cancer Institute discovers a 700-year-old mutation that makes a person resistant to HIV infection. From Evolution: "Evolutionary Arms Race."

In this video segment from 'Greater Boston,' Liz Lombard describes her struggle with a painful, progressive autoimmune disease called scleroderma. Scleroderma is rare, so Lombard was surprised to learn that other people in her South Boston neighborhood also had the disease. Health officials explain that there is a genetic predisposition to scleroderma, and there may be environmental factors involved as well. However, officials don't know whether this particular cluster is a result of environmental hazards or simply a coincidence. Includes background essay and discussion questions. [3:22]

When do the actions of one branch of the federal government unconstitutionally intrude upon the powers of another branch? This article surveys the history of this question in historic Supreme Court cases.

This lesson describes the major components and functions of the immune system and the role of engineers in keeping the body healthy (e.g., vaccinations and antibiotics, among other things). This lesson also discusses how an astronaut's immune system is suppressed during spaceflight due to stress and other environmental factors.

Read a passage about our immune system and answer the follow-up questions.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Although repeatedly exposed to HIV, Steve Crohn's blood cells were never infected. Dr. David Ho investigates in this video segment from NOVA: "Surviving AIDS."

In this simulation the learner will design a sequence of experiments to
generate a coronavirus vaccine.