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 how the kidneys serve as the main osmoregulatory organs in mammalian systems
Describe the structure of the kidneys and the functions of the parts of the kidney
Describe how the nephron is the functional unit of the kidney and explain how it actively filters blood and generates urine
Detail the three steps in the formation of urine: glomerular filtration, tubular reabsorption, and tubular secretion

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

This lesson helps students explore the functions of the kidney and its place in the urinary system. Students learn how engineers design instruments to help people when kidneys are not functioning properly or when environmental conditions change, such as kidney function in space.