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 how electrons move through the electron transport chain and explain what happens to their energy levels during this process
Explain how a proton (H+) gradient is established and maintained by the electron transport chain

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

Describe how feedback inhibition would affect the production of an intermediate or product in a pathway
Identify the mechanism that controls the rate of the transport of electrons through the electron transport chain

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

Explain how plants absorb energy from sunlight
Describe short and long wavelengths of light
Describe how and where photosynthesis takes place within a plant

This 17-minute video lesson presents an overview of the Electron Transport Chain. [Biology playlist: Lesson 26 of 71].

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This 14-minute video lesson presents an introduction to cellular respiration, glycolysis, the Kreb's Cycle, and the electron transport chain. [Biology playlist: Lesson 21 of 71].

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Describes the light reactions, the first stage of photosynthesis.

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Cellular respiration is the process by which our bodies convert glucose from food into energy in the form of ATP (adenosine triphosphate). Start by exploring the ATP molecule in 3D, then use molecular models to take a step-by-step tour of the chemical reactants and products in the complex biological processes of glycolysis, the Krebs cycle, the Electron Transport Chain, and ATP synthesis. Follow atoms as they rearrange and become parts of other molecules and witness the production of high-energy ATP molecules.

In this lesson, students learn about the basics of cellular respiration. They also learn about the application of cellular respiration to engineering and bioremediation. And, students are introduced to the process of bioremediation and several examples of how bioremediation is used during the cleanup of environmental contaminants.

Explore the specific reactions that happen during the cellular respiration process.

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This pathway provides an introduction to cellular metabolism, including a comparison of the processes of photosynthesis and cellular respiration. For a deeper look at this topic, we recommend the pathways Metabolism, Cellular Respiration and The Biological Process of Photosynthesis from the OpenStax textbook Biology for AP® Courses.

Students learn about the basic principles of electromicrobiology—the study of microorganisms’ electrical properties—and the potential that these microorganisms may have as a next-generation source of sustainable energy. They are introduced to one such promising source: microbial fuel cells (MFCs). Using the metabolisms of microbes to generate electrical current, MFCs can harvest bioelectricity, or energy, from the processes of photosynthesis and cellular respiration. Students learn about the basics of MFCs and how they function as well as the chemical processes of photosynthesis and cellular respiration