Students compare and contrast passive and active transport by playing a game to model this phenomenon. Movement through cell membranes is also modeled, as well as the structure and movement typical of the fluid mosaic model of the cell membrane. Concentration gradient, sizes, shapes and polarity of molecules determine the method of movement through cell membranes. This activity is associated with the Test your Mettle phase of the legacy cycle.

This activity first asks the students to study the patterns of bird flight and understand that four main forces affect the flight abilities of a bird. They will study the shape, feather structure, and resulting differences in the pattern of flight. They will then look at several articles that feature newly designed planes and the birds that they are modeled after. The final component of this activity is to watch the Nature documentary, "Raptor Force" which chronicles the flight patterns of birds, how researchers study these animals, and what interests our military and aeronautical engineers about these natural adaptations. This activity serves as an extension to the biomimetics lesson. Although students will not be using this information in the design process for their desert resort, it provides interesting information pertaining to the current use of biomimetics in the field of aviation. Students may extend their design process by using this information to create a means of transportation to and from the resort if they chose to.

In this unit, students learn about the form and function of the human heart through lecture, research and dissection. Following the steps of the Legacy Cycle, students brainstorm, research, design and present viable solutions to various heart conditions as presented through a unit challenge. Additionally, students study how heart valves work and investigate how faulty valves can be replaced with new ones through advancements in engineering and technology. This unit demonstrates to students how and why the heart is such a powerful organ in our bodies

The lesson begins with a demonstration introducing students to the force between two current carrying loops, comparing the attraction and repulsion between the loops to that between two magnets. After formal lecture on Ampere's law, students begin to use the concepts to calculate the magnetic field around a loop. This is applied to determine the magnetic field of a toroid, imagining a toroid as a looped solenoid.

This final lesson in the unit culminates with the Go Public phase of the legacy cycle. In the associated activities, students use linear models to depict Hooke's law as well as Ohm's law. To conclude the lesson, students apply they have learned throughout the unit to answer the grand challenge question in a writing assignment.

Students explore Hooke's law while working in small groups at their lab benches. They collect displacement data for springs with unknown spring constants, k, by adding various masses of known weight. After exploring Hooke's law and answering a series of application questions, students apply their new understanding to explore a tissue of known surface area. Students then use the necessary relationships to depict a cancerous tumor amidst normal tissue by creating a graph in Microsoft Excel.

The study of biomimicry and sustainable design promises great benefits in design applications, offering cost-effective, resourceful, non-polluting avenues for new enterprise. An important final caveat for students to understand is that once copied, species are not expendable. Biomimicry is intended to help people by identifying natural functions from which to pattern human-driven services. Biomimicry was never intended to replace species. Ecosystems remain in critical need of ongoing protection and biodiversity must be preserved for the overall health of the planet. This activity addresses the negative ramifications of species decline. For example, pollinators such as bees are a vital work force in agriculture. They perform an irreplaceable task in ensuring the harvest of most fruit and vegetable crops. In the face of the unexplained colony collapse disorder, we are only now beginning to understand how invaluable these insects are in keeping food costs down and even making the existence of these foods possible for humans.

With a continued focus on the Sonoran Desert, students are introduced to the concepts of biomes, limiting factors (resources), carrying capacity and growth curves through a PowerPoint® presentation. Abiotic factors (temperature, annual precipitation, seasons, etc.) determine the biome landscape. The vegetative component, as producers, determines the types of consumers that form its various communities. Students learn how the type and quantity of available resources defines how many organisms can be supported within the community, as well as its particular resident species. Students use mathematical models of natural relationships (in this case, sigmoid and exponential growth curves) to analyze population information and build upon it. With this understanding, students are able to explain how carrying capacity is determined by the limiting factors within the community and feeding relationships. By studying these ecological relationships, students see the connection between ecological relationships of organisms and the fundamentals of engineering design, adding to their base of knowledge towards solving the grand challenge posed in this unit.

Students are introduced to the concepts of biomimicry and sustainable design. Countless examples illustrate the wisdom of nature in how organisms are adapted for survival, such as in body style, physiological processes, water conservation, thermal radiation and mutualistic relationships, to assure species perpetuation. Students learn from articles and videos, building a framework of evidence substantiating the indisputable fact that organisms operate "smarter" and thus provide humans with inspiration in how to improve products, systems and cities. As students focus on applying the ecological principles of the previous lessons to the future design of our human-centered world, they also learn that often our practices are incapable of replicating the precision in which nature completes certain functions, as evidenced by our dependence on bees as pollinators of the human food supply. The message of biomimicry is one of respect: study to improve human practices and ultimately protect natural systems. This heightened appreciation helps students to grasp the value of industry and urban mimetic designs to assure protection of global resources, minimize human impact and conserve nonrenewable resources. All of these issues aid students in creating a viable guest resort in the Sonoran Desert.

This lesson begins with a demonstration prompting students to consider how current generates a magnetic field and the direction of the field that is generated. Through formal lecture, students learn Biot-Savart's law in order to calculate, most simply, the magnetic field produced in the center of a circular current carrying loop. For applications, students find it is necessary to integrate the field produced over all small segments in an actual current carrying wire.

Students study how heart valves work and investigate how valves that become faulty over time can be replaced with advancements in engineering and technology. Learning about the flow of blood through the heart, students are able to fully understand how and why the heart is such a powerful organ in our bodies.

In their reading from activity 1 of this unit, students should have discovered the term "logarithm." It is at this point that they begin their study of logarithms. Specifically, students examine the definition, history and relationship to exponents; they rewrite exponents as logarithms and vice versa, evaluating expressions, solving for a missing piece. Students then study the properties of logarithms (multiplication/addition, division/subtraction, exponents). They complete a set of practice problems to apply the skills they have learned (rewriting logarithms and exponents, evaluating expressions, solving/examining equations for a missing variable.) Then they complete a short quiz covering what they have studied thus far concerning logarithms (problems similar to the practice problems). They consider how what they have learned moves them closer to answering the unit's challenge question.

Students revisit the mathematics required to find bone mineral density, to which they were introduced in lesson 2 of this unit. They learn the equation to find intensity, Beer's law, and how to use it. Then they complete a sheet of practice problems that use the equation.

Students examine an image produced by a cabinet x-ray system to determine if it is a quality bone mineral density image. They write in their journals about what they need to know to be able to make this judgment. Students learn about what bone mineral density is, how a BMD image can be obtained, and how it is related to the x-ray field. Students examine the process used to obtain a BMD image and how this process is related to mathematics, primarily through logarithmic functions. They study the relationship between logarithms and exponents, the properties of logarithms, common and natural logarithms, solving exponential equations and Beer's law.

This lesson discusses the result of a charge being subject to both electric and magnetic fields at the same time. It covers the Hall effect, velocity selector, and the charge to mass ratio. Given several sample problems, students learn to calculate the Hall Voltage dependent upon the width of the plate, the drift velocity, and the strength of the magnetic field. Then students learn to calculate the velocity selector, represented by the ratio of the magnitude of the fields assuming the strength of each field is known. Finally, students proceed through a series of calculations to arrive at the charge to mass ratio. A homework set is included as an evaluation of student progress.

Students work in groups to create soap bubbles on a smooth surface, recording their observations from which they formulate theories to explain what they see (color swirls on the bubble surfaces caused by refraction). Then they apply this theory to thin films in general, including porous films used in biosensors, listing factors that could change the color(s) that become visible to the naked eye, and learn how those factors can be manipulated to give information on gene detection. Finally (by experimentation or video), students see what happens when water is dropped onto the surface of a Bragg mirror.

Students design and construct electromagnets that must pick up 10 staples. They begin with only minimal guidance, and after the basic concept is understood, are informed of the properties that affect the strength of that magnet. They conclude by designing their own electromagnets to complete the challenge of separating scrap steel from scrap aluminum for recycling, and share it with the class.

This lab demonstrates Ohm's law as students set up simple circuits each composed of a battery, lamp and resistor. Students calculate the current flowing through the circuits they create by solving linear equations. After solving for the current, I, for each set resistance value, students plot the three points on a Cartesian plane and note the line that is formed. They also see the direct correlation between the amount of current flowing through the lamp and its brightness.

Students color-code a schematic of a cell and its cell membrane structures. Then they complete the "Build-a-Membrane" activity found at http://learn.genetics.utah.edu. This reinforces their understanding of the structure and function of animal cells, and shows them the importance of being able to construct a tangible model of something that is otherwise difficult to see.

The final activity of this unit, which integrates the Keepers of the Gate unit through the Go Public challenge, involves students taking part in experimental design. They design a lab that answers the challenge question: "You are spending the night with your grandmother when your throat starts to feel sore. Your grandma tells you to gargle with salt water and it will feel much better. Thinking this is an old wive's tale, you scoff, but when you try it later that night it works! Why?" Students must have their plan approved by the instructor before they begin. A formal lab write-up is due as part of the laboratory investigation.