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 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.

Students learn about the different structures that comprise cell membranes, fulfilling part of the Research and Revise stages of the legacy cycle. They view online animations of cell membrane dynamics (links provided). Then they observe three teacher demonstrations that illustrate diffusion and osmosis concepts, as well as the effect of movement through a semi-permeable membrane using Lugol's solution.

The computer program's simulation of a Sonoran desert community should ultimately strengthen the student's comprehension of what is required for a natural ecosystem to sustain itself (remain in balance). This computer simulation program has great flexibility. It allows the student to manipulate the population numbers of five Sonoran Desert species. A species natural history attachment provides vital information for the students to familiarize themselves with each species' behaviors, its niche and food resource needs. The program includes two producers, the Saguaro cactus and the Ironwood Tree. It also includes 3 consumers, but their interactions both toward the producers and each other differ. The community's ability to remain in balance and sustain all five species so that none die out rests on the student's assessment skills enabling him to correctly identify these dependencies. The student learns by trial and error as he continues to fine tune the ecosystem that he maintains stewardship of.

Is the food chain shown above accurate? Does the first link depict a producer, the second link a herbivore, and the third link an omnivore / carnivore? Students must correctly determine whether a species is a producer or consumer, and what type of consumer; herbivore, omnivore, or carnivore. Students are provided with a list of Sonoran Desert species and asked to construct, within their groups, several food chains. These food chains are then be used to construct a food web. In order to complete this activity, students must first research the individual species to understand their feeding habits.

Students are challenged to design a permanent guest village within the Saguaro National Park in Arizona. The design must provide a true desert experience to visitors while emphasizing sustainable design, protection of the natural environment, and energy and resource conservation. To successfully address and respond to this challenge, students must acquire an understanding of desert ecology, environmental limiting factors, species adaptations and resource utilization. Following theintroduction, students generate ideas and consider the knowledge required to complete the challenge. The lectures and activities that follow serve to develop this level of comprehension. To introduce the concepts of healthy ecosystems, biomimetics and the importance of sustainable environmental design, students watch three video clips of experts. These clips provide direction for student research and challenge design solutions.

The Challenge Question of the Legacy Cycle draws the student into considering the engineering ingenuity of nature. It will force him to analyze, appreciate and understand the wisdom of these designs as the student team focuses on meeting each of the challenge's requirements. The student is asked, with his team members, to envision a sustainable design for a future guest village within the Saguaro National Park, outside of Tucson, Arizona. What issues need to be addressed to support the comforts of park visitors without compromising the natural resources or endangering the endemic species of the area? A deeper scope of application will reveal extensions of this design in the incorporation of urban planning and systems design. It also strengthens the concept of manufacturing and building without producing waste or pollution.

Students are presented with a hypothetical scenario that delivers the unit's Grand Challenge Question: To apply an understanding of nanoparticles to treat, detect and protect against skin cancer. Towards finding a solution, they begin the research phase by investigating the first research question: What is electromagnetic energy? Students learn about the electromagnetic spectrum, ultraviolet radiation (including UVA, UVB and UVC rays), photon energy, the relationship between wave frequency and energy (c = λν), as well as about the Earth's ozone-layer protection and that nanoparticles are being used for medical applications. The lecture material also includes information on photo energy and the dual particle/wave model of light. Students complete a problem set to calculate frequency and energy.

To become familiar with the transfer of energy in the form of quantum, students perform flame tests, which is one way chemical engineers identify elements by observing the color emitted when placed in a flame. After calculating and then preparing specific molarity solutions of strontium chloride, copper II chloride and potassium chloride (good practice!), students observe the distinct colors each solution produces when placed in a flame, determine the visible light wavelength, and apply that data to identify the metal in a mystery solution. They also calculate the frequency of energy for the solutions.

With a continued focus on the Sonoran Desert, students are introduced to the concepts of food chains and food webs through a PowerPoint® presentation. They learn the difference between producers and consumers and study how these organisms function within their communities as participants in various food chains. They further understand ecosystem differences by learning how multiple food chains link together to form intricate and balanced food webs. At lesson end, students construct food webs using endemic desert species.

Student teams design and conduct quality-control experiments to test the reliability of several ultraviolet protection factors. Students use UV-detecting beads in their experimental designs to test the effectiveness of various types of sunscreens and sunblock. For example, they might examine zinc oxide nanoparticles versus traditional organic sun protection factors. UV intensity is quantitatively measured by UVA and UVB Vernier sensors, and students record and graph their results. By designing and conducting this experiment, students compare various substances, while learning about quality control.

Students are presented with an engineering challenge: To design a sustainable guest village within the Saguaro National Park in Arizona. Through four lessons and six associated activities, they study ecological relationships with an emphasis on the Sonoran Desert. They examine species adaptations. They come to appreciate the complexity and balance that supports the exchange of energy and matter within food webs. Then students apply what they have learned about these natural relationships to the study of biomimicry and sustainable design. They study the flight patterns of birds and relate their functional design to aeronautical engineering. A computer simulation model is also incorporated into this unit and students use this program to examine perturbations within a simple ecosystem. The solution rests within the lessons and applications of this unit.

Students apply the knowledge gained from the previous lessons and activities in this unit to write draft grant proposals to the U.S. National Institutes of Health outlining their ideas for proposed research using nanoparticles to protect against, detect or treat skin cancer. Through this exercise, students demonstrate their understanding of the environmental factors that contribute to skin cancer, the science and mathematics of UV radiation, the anatomy of human skin, current medical technology applications of nanotechnology and the societal importance of funding research in this area, as well as their communication skills in presenting plans for specific nanoscale research they would conduct using nanoparticles.

Students learn about the biomedical use of nanoparticles in the detection and treatment of cancer, including the use of quantum dots and lasers that heat-activate nanoparticles. They also learn about electrophoresis a laboratory procedure that uses an electric field to move tiny particles through a channel in order to separate them by size. They complete an online virtual mini-lab, with accompanying worksheet, to better understand gel electrophoresis. This prepares them for the associated activity to write draft research proposals to use nanoparticles to protect against, detect or treat skin cancer.

Students explore the applications of quantum dots by researching a journal article and answering framing questions used in a classwide discussion. This "Harkness-method" discussion helps students become critical readers of scientific literature.

Towards finding a solution to the unit's Grand Challenge Question about using nanoparticles to detect, treat and protect against skin cancer, students continue the research phase in order to answer the next research questions: What is the structure and function of skin? How does UV radiation affect the chemical reactions that go on within the skin? After seeing an ultraviolet-sensitive bead change color and learning how they work, students learn about skin anatomy and the effects of ultraviolet radiation on human skin, pollution's damaging effect on the ozone layer that can lead to increases in skin cancer, the UV index, types of skin cancer, ABCDEs of mole and lesion evaluation, and the sun protection factor (SPF) rating system for sunscreens. This prepares students to conduct the associated activity, in which they design quality-control experiments to test SPF substances.

This unit on nanoparticles engages students with a hypothetical Grand Challenge Question that asks about the skin cancer risk for someone living in Australia, given the local UV index and the condition of the region's ozone layer. The question asks how nanoparticles might be used to help detect, treat and protect people from skin cancer. Through three lessons, students learn about the science of electromagnetic radiation and energy waves, human skin and its response to ultraviolet radiation, and the state of medical nanotechnology related to skin cancer. Through three hands-on activities, students perform flame tests to become familiar with the transfer of energy in quantum form, design and conduct their own quality-control experiments to test sun protection factors (SPFs), and write nanotechnology grant proposals.