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.

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.

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

Discuss the role of carbohydrates in cells and in the extracellular materials of animals and plants
Explain carbohydrate classifications
List common monosaccharides, disaccharides, and polysaccharides

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

Describe the four major types of lipids
Explain the role of fats in storing energy
Differentiate between saturated and unsaturated fatty acids
Describe phospholipids and their role in cells
Define the basic structure of a steroid and some steroid functions
Explain how cholesterol helps maintain the plasma membrane's fluid nature

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

Describe nucleic acids' structure and define the two types of nucleic acids
Explain DNA's structure and role
Explain RNA's structure and roles

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

Describe the functions proteins perform in the cell and in tissues
Discuss the relationship between amino acids and proteins
Explain the four levels of protein organization
Describe the ways in which protein shape and function are linked

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

Understand macromolecule synthesis
Explain dehydration (or condensation) and hydrolysis reactions

Explore and review the biological molecules necessary for life.

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All cells, organs and tissues of a living organism are built of molecules. Some of them are small, made from only a few atoms. There is, however, a special class of molecules that make up and play critical roles in living cells. These molecules can consist of many thousands to millions of atoms. They are referred to as macromolecules (or large biomolecules).