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 role of different glands in the endocrine system
Explain how the different glands work together to maintain homeostasis

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

Explain how hormones work
Discuss the role of different types of hormone receptors

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

Explain how hormones regulate the excretory system
Discuss the role of hormones in the reproductive system
Describe how hormones regulate metabolism
Explain the role of hormones in different diseases

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

Explain how hormone production is regulated
Discuss the different stimuli that control hormone levels in the body

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

List the different types of hormones
Explain their role in maintaining homeostasis

This comprehensive study guide covers the main terms and concepts needed for a unit on the endocrine system.

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This pathway provides and introduction to some of the systems of the body and the concept of homeostasis.

In this activity, students are divided into a group of hormones and a group of receptors. The hormones have to find their matching receptors, and the pair, once matched, perform a given action. This activity helps students learn about the specificity of hormone-receptor interactions within the endocrine system.

This scrollable introduces the concept that cells can communicate via signaling molecules in a process called cell signaling. Communication between cells can lead to a variety of changes in the cell, from alterations to its growth, structure or metabolism. When cell signaling pathways don’t function properly, disease can result.

A video lesson explaining the structure and function of the human body's major organ systems. [5:58]

Students learn how the endocrine system works and compare it to the mail delivery system. Students discuss the importance of communication in human body systems and relate that to engineering and astronauts.