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:Describe an open and closed circulatory systemDescribe interstitial fluid and hemolymphCompare and contrast the organization and evolution of the vertebrate circulatory system.

This lesson describes how the circulatory system works, including the heart, blood vessels and blood. Students learn about the chambers and valves of the heart, the difference between veins and arteries, and the different components of blood. This lesson also covers the technology engineers have developed to repair the heart if it is damaged. Students also understand how the circulatory system is affected during spaceflight (e.g., astronauts lose muscle in their heart during space travel).

This lesson contains background about the blood vascular system and the heart. Also, the different sizes of capillaries, veins, and arteries, and how they affect blood flow through the system. We will then proceed to talk about the heart's function in the blood vascular system. This will lead into a discussion of heart valves, how they work and what might cause them to fail. Then we will discuss prosthetic heart valves.