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:Define species and describe how species are identified as differentDescribe genetic variables that lead to speciationIdentify prezygotic and postzygotic reproductive barriersExplain allopatric and sympatric speciationDescribe adaptive radiation

In some cities, especially large cities such as Los Angeles or Mexico City, visible air pollution is a major problem, both for human health and the environment. A variety of sources contribute to air pollution, but personal vehicles account for one of the main sources. Though each car has relatively low emissions when compared to vehicles of the 1970s, there are so many more cars on the road now that their emissions play a large role in overall pollution. In this activity, students think about alternate ways to power a vehicle to reduce emissions. Student teams design an eco-friendly car using the engineering design process, and make a presentation to showcase their product.

Students investigate different forms of hybrid engines as well as briefly conclude a look at the different forms of potential energy, which concludes the Research and Revise step of the legacy cycle. Students are introduced to basic circuit schematics and apply their understanding of the difference between series and parallel circuits to current research on hybrid cars.

Students gain perspective on the intended purpose of hydraulic accumulators and why they might be the next best innovation for hybrid passenger vehicles. They learn about how hydraulic accumulators and hydraulic systems function, specifically how they conserve energy by capturing braking energy usually lost as heat. Students are given the engineering challenge to create small-scale models from which their testing results could be generalized to large-scale latex tubing for a hydraulic accumulator. After watching a video clip of an engineer talking about his lab-based model to test the feasibility of using an elastomer as an energy accumulator, they brainstorm ideas about how latex can be used in a hydraulic system and how they could test the strength of latex for use in a hydraulic accumulator. The concepts of kinetic energy and energy density are briefly discussed.

Looking at transportation and the environment, students learn that some human-made creations, such as vehicles, can harm the environment. They also learn about alternative fuels and vehicles designed by engineers to minimize pollution. The associated hands-on activity gives students a chance to design their own eco-friendly vehicle.

Students learn more about magnetism, and how magnetism and electricity are related in electromagnets. They learn the fundamentals about how simple electric motors and electromagnets work. Students also learn about hybrid gasoline-electric cars and their advantages over conventional gasoline-only-powered cars.