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:

Identify the macronutrients needed by prokaryotes, and explain their importance
Describe the ways in which prokaryotes get energy and carbon for life processes
Describe the roles of prokaryotes in the carbon and nitrogen cycles

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

Discuss the biogeochemical cycles of water, carbon, nitrogen, phosphorus, and sulfur
Explain how human activities have impacted these cycles and the potential consequences for Earth

Review some of the cycles that recycle matter through Earth's biospheres.

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College-level online course highlighting the fundamentals of ecology. Course topics include coevolution of the biosphere, geosphere, atmosphere, and hydrosphere; photosynthesis and respiration; and the carbon, nitrogen, and water cycles. Other topics include energy flow through the biosphere and changes in ecosystems. This course features selected lecture notes, assignments with solutions, projects and examples, and exams with solutions.

Students explore the concept of biodegradability by building and observing model landfills to test the decomposition of samples of everyday garbage items. They collect and record experiment observations over five days, seeing for themselves what happens to trash when it is thrown "away" in a landfill environment. This shows them the difference between biodegradable and non-biodegradable and serves to introduce them to the idea of composting. Students also learn about the role of engineering in solid waste management.

In this module, students will learn about the cycles of nature (water, carbon, nitrogen, and phosphorus) that support the flow of nutrient matter through an ecosystem, as distinct from the flow of energy. Includes learning activities, a study guide, flashcards, and quizzes.

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Describes the nitrogen cycle.

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Describes the nitrogen cycle.

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Review the main concepts of the nitrogen cycle in this study guide.

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Students learn about energy and nutrient flow in various biosphere climates and environments. They learn about herbivores, carnivores, omnivores, food chains and food webs, seeing the interdependence between producers, consumers and decomposers. Students are introduced to the roles of the hydrologic (water), carbon, and nitrogen cycles in sustaining the worlds' ecosystems so living organisms survive. This lesson is part of a series of six lessons in which students use their growing understanding of various environments and the engineering design process, to design and create their own model biodome ecosystems.

If the atmosphere is about 80% Nitrogen (N2), but plants cannot use that form, how do they get nitrogen? In this unit, students plant and care for soybeans under one of five different nitrogen/microbe regimes.

As the plants grow, students analyze and maintain records of their plant’s progress. Students will become familiar with the vegetative and reproductive stages of the soybean (more information and pictures of these stages can be found at the OSU crop extensions sites). Students keep records of the dates in which they observe these reproductive transitions. This unit features 2 lessons and 7 files. Lessons are aligned to NGSS.

Learn about the Nitrogen cycle, and understand how it affects the ecosystem.

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Like water and carbon, nitrogen is also repeatedly recycled through the biosphere. This process is called the nitrogen cycle. Learn more about the nitrogen cycle in this learning module produced by CK-12.

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Students use everyday building materials sand, pea gravel, cement and water to create and test pervious pavement. They learn what materials make up a traditional, impervious concrete mix and how pervious pavement mixes differ. Groups are challenged to create their own pervious pavement mixes, experimenting with material ratios to evaluate how infiltration rates change with different mix combinations.

An overview of the nitrogen cycle, covering nitrogen fixation, decay, nitrification, denitrification, and more.