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 why and how passive transport occurs
Understand the osmosis and diffusion processes
Define tonicity and its relevance to passive transport

Students learn about various crystals, such as kidney stones, within the human body. They also learn about how crystals grow and ways to inhibit their growth. They also learn how researchers such as chemical engineers design drugs with the intent to inhibit crystal growth for medical treatment purposes and the factors they face when attempting to implement their designs. A day before presenting this lesson to students, conduct the associated activity, Rock Candy Your Body.

In the following video Paul Andersen explains how the dissolution of a solute in a solution can be explained as a reversible reaction. Bonds in the solid solute are broken and the ions are dissolved in a solution. The Ksp (or solubility product constant) can be used to explain the solubility of various salts. [7:06]

We can combine our knowledge of acids and bases, equilibrium, and neutralization reactions to understand buffers and titrations. Solubility equilibria will build on concepts from solubility, precipitation, and equilibrium.

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 concept-building module contains a variety of simulations for exploring factors that cause molecules to attract each other. It was developed to help secondary students understand both polar and non-polar covalent bonding. Users can manipulate models to see how the strength of attraction is affected by distance from one molecule to another, by heating the substance, and by mixing polar and non-polar substances. Part II of the activity is devoted to hydrogen bonds, and explores why water is one of the most important molecules for life's existence. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

Students develop and conduct an experiment using the law of conservation of mass to determine whether or not gum should be considered food. Students will compare the mass swallowed for sugar and sugar-free gum. This could be used to discuss solubility.

This lesson focuses on how food packages are designed and made. Students will learn three of the main functions of a food package. They will learn what is necessary of the design and materials of a package to keep food clean, protect or aid in the physical and chemical changes that can take place in a food, and identify a food appealingly. Then, in the associated activity, the students will have the opportunity to become packaging engineers by designing and building their own food package for a particular type of food.

Students are challenged to think as biomedical engineers and brainstorm ways to administer medication to a patient who is unable to swallow. They learn about the advantages and disadvantages of current drug delivery methods—oral, injection, topical, inhalation and suppository—and pharmaceutical design considerations, including toxicity, efficacy, size, solubility/bioavailability and drug release duration. They apply their prior knowledge about human anatomy, the circulatory system, polymers, crystals and stoichiometry to real-world biomedical applications. A Microsoft® PowerPoint® presentation and worksheets are provided. This lesson prepares students for the associated activity in which they create and test large-size drug encapsulation prototypes to provide the desired delayed release and duration timing.

Students learn how crystallization and inhibition occur by examining calcium oxalate crystals with and without inhibitors that are capable of altering crystallization. Kidney stones are composed of calcium oxalate crystals, and engineers and doctors experiment with these crystals to determine how growth is affected when a potential drug is introduced. Students play the role of engineers by trying to determine which inhibitor would be the best for blocking crystallization.

In this interactive lesson, learn what the "physical properties" of matter are and how can they be measured and observed.

This lesson will allow students to explore an important role of environmental engineers: cleaning the environment. Students will learn details about the Exxon Valdez oil spill, which was one of the most publicized and studied environmental tragedies in history. In the accompanying activity, they will try many "engineered" strategies to clean up their own manufactured oil spill and learn the difficulties of dealing with oil released into our waters.

This hands-on experiment will provide students with an understanding of the issues that surround environmental cleanup. Students will create their own oil spill, try different methods for cleaning it up, and then discuss the merits of each method in terms of effectiveness (cleanliness) and cost. They will be asked to put themselves in the place of both an environmental engineer and an oil company owner who are responsible for the clean-up.

Student groups are challenged to create food packages for specific foods. They focus on three components in the design of their food packages; the packages must keep the food clean, protect or aid in the physical and chemical changes that can take place in the food, and present the food appealingly. They design their packaging to meet these requirements.

What determines the concentration of a solution? Learn about the relationships between moles, liters, and molarity by adjusting the amount of solute and solution volume. Change solutes to compare different chemical compounds in water.

Add different salts to water, then watch them dissolve and achieve a dynamic equilibrium with solid precipitate. Compare the number of ions in solution for highly soluble NaCl to other slightly soluble salts. Relate the charges on ions to the number of ions in the formula of a salt. Calculate Ksp values.

Students see and learn how crystallization and inhibition occur by making sugar crystals with and without additives in a supersaturation solution, testing to see how the additives may alter crystallization, such as by improving crystal growth by more or larger crystals. After three days, students analyze the differences between the control crystals and those grown with additives, researching and attempting to deduce why certain additives blocked crystallization, showed no change or improved growth. Students relate what they learn from the rock candy experimentation to engineering drug researchers who design medicines for targeted purposes in the human body. Conduct the first half of this activity one day before presenting the associated lesson, Body Full of Crystals. Then conduct the second half of the activity.

Compare the size and shape of crystals grown in different temperature conditions in this science fair project. The Science Buddies project ideas are set up consistently beginning with an abstract, objective, and introduction, followed by a section on terms, concepts, and questions, bibliography, list of materials and equipment, experimental procedure, suggestions on how to vary the experiment, plus a focus on the sort of careers this experiment might relate to.