Students learn about mutations to both DNA and chromosomes, and uncontrolled changes to the genetic code. They are introduced to small-scale mutations (substitutions, deletions and insertions) and large-scale mutations (deletion duplications, inversions, insertions, translocations and nondisjunctions). The effects of different mutations are studied as well as environmental factors that may increase the likelihood of mutations. A PowerPoint® presentation and pre/post-assessments are provided.

Using Avida-ED freeware, students control a few factors in an environment populated with digital organisms, and then compare how changing these factors affects population growth. They experiment by altering the environment size (similar to what is called carrying capacity, the maximum population size that an environment can normally sustain), the initial organism gestation rate, and the availability of resources. How systems function often depends on many different factors. By altering these factors one at a time, and observing the results, students are able to clearly see the effect of each one.

This lesson is the second of two that explore cellular respiration and population growth in yeasts. In the first lesson, students set up a simple way to indirectly observe and quantify the amount of respiration occurring in yeast-molasses cultures. Based on questions that arose during the first lesson and its associated activity, in this lesson students work in small groups to design experiments that will determine how environmental factors affect yeast population growth.

In this activity, learners explore how different deodorants work. Learners treat agar plates with different types of deodorants and compare the bacteria growth on the plates to the control sample.

Students learn that engineers develop different polymers to serve various functions and are introduced to selectively permeable membranes. In a warm-up activity, they construct models of selectively permeable membranes using common household materials, and are reminded about simple diffusion and passive transport. In the main activity, student pairs test and compare the selective permeability of everyday polymer materials engineered for food storage (including plastic grocery bags, zipper sandwich bags, and plastic wrap) with various in-solution molecules (iodine, corn starch, food coloring, marker dye), assess how the polymer’s permeability relates to its function/purpose, and compare that to the permeability of dialysis tubing (which simulates a cell membrane).

Students learn about water quality testing and basic water treatment processes and technology options. Biological, physical and chemical treatment processes are addressed, as well as physical and biological water quality testing, including testing for bacteria such as E. coli.

Students experience the engineering design process as they design, fabricate, test and redesign their own methods for encapsulation of a (hypothetical) new miracle drug. As if they are engineers, teams make large-size prototypes to test proof of concept. They use household materials (tape, paper towels, plastic wrap, weed-barrier fabric, glues, etc.) to attach a coating to a porous "shell" (a perforated plastic Wiffle® ball) containing the medicine (colored drink mix powder). The objective is to delay the drug release by a certain time and have a long release duration—patterned after the timed release requirements of many real-world pharmaceuticals that are released from a polymer shell via diffusion in the body. Guided by a worksheet, teams go through at least three design/test iterations, aiming to achieve a solution close to the target time release constraints.

Students are introduced to an engineering challenge in which they are given a job assignment to separate three types of apples. However, they are unable to see the color differences between the apples, and as a result, they must think as engineers to design devices that can be used to help them distinguish the apples from one another. Solving the challenge depends on an understanding of wave properties and the biology of sight. After being introduced to the challenge, students form ideas and brainstorm about what background knowledge is required to solve the challenge. A class discussion produces student ideas that can be grouped into broad subject categories: waves and wave properties, light and the electromagnetic spectrum, and the structure of the eye.

Students learn about homeostasis and create models by constructing simple feedback systems using Arduino boards, temperature sensors, LEDs and Arduino code. Starting with pre-written code, students instruct LEDs to activate in response to the sensor detecting a certain temperature range. They determine appropriate temperature ranges and alter the code accordingly. When the temperature range is exceeded, a fan is engaged in order to achieve a cooling effect. In this way, the principle of homeostasis is demonstrated. To conclude, students write summary paragraphs relating their models to biological homeostasis.

For this maker challenge, students become biomedical engineers who design, create, and test a medical device that measures a patient’s pulse using a microcontroller, LED, and light sensor. Students use data collected from the device they build to determine how to best visualize the results, so that a doctor can view the patient’s pulse on the computer screen. During the challenge, students learn about basic coding, the capabilities of microcontrollers, how sensors gather data, how the human circulatory system works, and how to plot real data. Finally, students are challenged to make their systems portable so that they create wearable health technology. This is a great project for a high school senior design team project.

Students apply everything they have learned over the course of the associated lessons about waves, light properties, the electromagnetic spectrum, and the structure of the eye, by designing devices that can aid color blind people in distinguishing colors. Students learn about the engineering design process and develop three possible solutions to the engineering design challenge outlined in lesson 1 of this unit. They create posters to display their three design ideas and the comparisons used to select the best design. Then, students create brochures for their final design ideas, and "sell" the ideas to their "client." Through this activity, students complete the legacy cycle by "going public" with the creation of their informative posters and brochures that explain their designs, as well as color blindness and how people see color, in "client" presentations.

Students set up a simple way to indirectly observe and quantify the amount of respiration occurring in yeast-molasses cultures. Each student adds a small amount of baking yeast to a test tube filled with diluted molasses. A second, smaller test tube is then placed upside-down inside the solution. As the yeast cells respire, the carbon dioxide they produce is trapped inside the inverted test tube, producing a growing bubble of gas that is easily observed and measured. Students are presented with the procedure for designing an effective experiment; they learn to think critically about experimental results and indirect observations of experimental events.