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.

In this unit, students look at the components of cells and their functions and discover the controversy behind stem cell research. The first lesson focuses on the difference between prokaryotic and eukaryotic cells. In the second lesson, students learn about the basics of cellular respiration. They also learn about the application of cellular respiration to engineering and bioremediation. The third lesson continues students' education on cells in the human body and how (and why) engineers are involved in the research of stem cell behavior.

In this lesson, students learn about the basics of cellular respiration. They also learn about the application of cellular respiration to engineering and bioremediation. And, students are introduced to the process of bioremediation and several examples of how bioremediation is used during the cleanup of environmental contaminants.

The topic of this video module is how to classify animals based on how closely related they are. The main learning objective is that students will learn how to make phylogenetic trees based on both physical characteristics and on DNA sequence. Students will also learn why the objective and quantitative nature of DNA sequencing is preferable when it come to classifying animals based on how closely related they are. Knowledge prerequisites to this lesson include that students have some understanding of what DNA is and that they have a familiarity with the base-pairing rules and with writing a DNA sequence.

This variation on the classic bird beak activity demonstrates variation of beak size within a population and shows how the proportion of big-, medium-, and small-beaked birds changes in response to the available types of food. The “birds” with binder clip “beaks” live in Clipland where the large population becomes divided into two smaller populations by a mountain range. Popcorn, lima beans and marbles are the three types of food available in the two areas. Food is spread out for the birds to eat and then after 15 seconds it is counted to see whether birds have gathered enough food to survive. The big billed birds need to eat more than the medium and small billed birds to survive and each bird needs to eat more than the minimum amount of food for survival to be able to reproduce. Four years pass during the simulation and students are asked to describe what happened to the Clipbird populations and what they think caused the changes. A link to Rosemary and Peter Grant’s research on finch populations in the Galapagos is identified for those teachers who want to connect the simulation to a real life example.

This activity provides an introduction to natural selection and the role of genetic variation by asking students to analyze illustrations of rock pocket mouse populations (dark/light fur) on different color substrates in the Sonoran Desert (light/dark) over time. Based on this evidence, and what they learn about variation and natural selection in the accompanying short film, students use this evidence to explain the change in the rock pocket mouse populations on the lava flow (dark substrate) over time. This is one of several classroom activities, focusing on related topics and varying in complexity, built around the short film. This ten minute film shows adaptive changes in rock pocket mouse populations, demonstrating the process of natural selection and can be accessed at http://www.hhmi.org/biointeractive/making-fittest-natural-selection-and-adaptation. The film is also available as an interactive video with embedded questions, which test students’ understanding as they watch the film.

Concepts of Biology is designed for the introductory biology course for nonmajors taught at most two- and four-year colleges. The scope, sequence, and level of the program are designed to match typical course syllabi in the market. Concepts of Biology includes interesting applications, features a rich art program, and conveys the major themes of biology.

In this activity, students examine how to grow plants the most efficiently. They imagine that they are designing a biofuels production facility and need to know how to efficiently grow plants to use in this facility. As a means of solving this design problem, they plan a scientific experiment in which they investigate how a given variable (of their choice) affects plant growth. They then make predictions about the outcomes and record their observations after two weeks regarding the condition of the plants' stem, leaves and roots. They use these observations to guide their solution to the engineering design problem. The biological processes of photosynthesis and transpiration are briefly explained to help students make informed decisions about planning and interpreting their investigation and its results.

This online interactive module of 10 pages or frames integrates textual information, 3D molecular models, interactive molecular simulations, and embedded assessment items to guide students in understanding the copying of DNA base sequences from translation to transcription into proteins within each cell. The module divides the exercises in to Day 1 and Day 2 time frames. Teachers can view student assessment responses by assigning the module within a class created within the Molecular Workbench application. This Java-based module must be downloaded to each computer.

Students learn how the process of soil solarization is used to pasteurize agricultural fields before planting crops. Soil solarization is a pest control technique in agriculture that uses the sun’s radiation to heat the soil and eliminate unwanted pests that could harm the crops. The approach is compared to other pest control methods such as fumigation and herbicide application, highlighting the respective benefits and drawbacks. In preparation for the associated hands-on activity on soil biosolarization, students learn how changing the variables involved in the solarizing process (such as the tarp material, soil water content and addition of organic matter) impacts the technique’s effectiveness. A PowerPoint® presentation and pre/post-quiz is provided.

This three-act film tells the story of the detective work that solved the mystery of what caused the disappearance of the dinosaurs at the end of the Cretaceous period. Shot on location in Italy, Spain, Texas, Colorado, and North Dakota, the film traces the uncovering of key clues that led to the discovery that an asteroid struck the Earth 66 million years ago, triggering a mass extinction of animals, plants, and microorganisms. Science practices in geology, physics, biology, chemistry and paleontology all contributed to the solution to this compelling mystery. Lesson plans are included that have students identify evidence and construct an explanation to tie it together. Summary questions are included at the end and a class discussion is recommended. (This activity will be the only one evaluated in this review.) Another resource is “Finding the Crater” where students “visit” different K-T boundary sites. There are also lessons where students analyze various characteristics of the asteroid such as its size and energy, chemical data about the asteroid, and the iridium fallout from an asteroid impact. A hands-on activity where students study the differences in foraminifera fossils below and above the K-T boundary is also included as well as an article that outlines more details about each of the discoveries covered in the film. You can view the film on the website or HHMI will send you a free DVD. Lesson plans including teacher notes and a student handout can be found at http://www.hhmi.org/biointeractive/following-trail-evidence.

In a multi-week experiment, student teams gather biogas data from the mini-anaerobic digesters that they build to break down different types of food waste with microbes. Using plastic soda bottles for the mini-anaerobic digesters and gas measurement devices, they compare methane gas production from decomposing hot dogs, diced vs. whole. They monitor and measure the gas production, then graph and analyze the collected data. Students learn how anaerobic digestion can be used to biorecycle waste (food, poop or yard waste) into valuable resources (nutrients, biogas, energy).

In this video module, students learn how scientists use genetic information from dogs to find out which gene (out of all 20,000 dog genes) is associated with any specific trait or disease of interest. This method involves comparing hundreds of dogs with the trait to hundreds of dogs not displaying the trait, and examining which position on the dog DNA is correlated with the trait (i.e. has one DNA sequence in dogs with the trait but another DNA sequence in dogs not displaying the trait). Students will also learn something about the history of dog breeds and how this history helps us find genes.

Scientists who are working to discover new medicines often use robots to prepare samples of cells, allowing them to test chemicals to identify those that might be used to treat diseases. Students will meet a scientist who works to identify new medicines. She created free software that ''looks'' at images of cells and determines which images show cells that have responded to the potential medicines. Students will learn about how this technology is currently enabling research to identify new antibiotics to treat tuberculosis. Students will complete hands-on activities that demonstrate how new medicines can be discovered using robots and computer software, starring the student as ''the computer.'' In the process, the students learn about experimental design, including positive and negative controls.

Students make edible models of algal cells as a way to tangibly understand the parts of algae that are used to make biofuels. The molecular gastronomy techniques used in this activity blend chemistry, biology and food for a memorable student experience. The models use sodium alginate, which forms a gel matrix when in contact with calcium or moderate acid, to represent the complex-carbohydrate-composed cell walls of algae. Cell walls protect the algal cell contents and can be used to make biofuels, although they are more difficult to use than the starch and oils that accumulate in algal cells. The liquid juice interior of the algal models represents the starch and oils of algae, which are easily converted into biofuels.

This activity demonstrates the effect of changes in the environment on the growth of plants. The plants are placed in environments such as high salinity, cold, heat, or drought and observe the different reactions (growth) of the plants to these conditions. Students discuss the desirability of breeding new types of plants that are better able to withstand these changes if they occur in the general environment. The objectives of this activity is to: 1. Plant, grow and maintain plants under different environmental treatment conditions. 2. Observe differences in plant growth between these treatments. 3. Compare the growth of treated plants with the growth of control plants

This biomimetic engineering challenge introduces students to the fields of nanotechnology and biomimicry. Students explore how to modify surfaces such as wood or cotton fabric at the nanoscale. They create specialized materials with features such as waterproofing and stain resistance. The challenge starts with student teams identifying an intended user and developing scenarios for using their developed material. Students then design and create their specialized material using everyday materials. Each students test each design under specific testing constraints to determine the hydrophobicity of the material. After testing, teams iterate ways to improve their self-cleaning superhydrophobic modification technique for their design. After iterating and testing their designs, students present their final product and results to the class.

To evaluate the different integumentary systems found in the animal kingdom, students conduct an exploratory research-based lab. During the activity, students create a model epidermis that contains phosphorescent powder and compare the results to a control model. After learning about the variations of integumentary systems—systems that comprise the skin and other appendages that act to protect animal bodies from damage—students act as engineers to mimic animal skin samples. Their goal is to create a skin sample that closely represents the animal they are mimicking while protecting the base ‘epidermis’ from UV light.

This video lesson shows students that math can play a role in understanding how an infectious disease spreads and how it can be controlled. During this lesson, students will see and use both deterministic and probabilistic models and will learn by doing through role-playing exercises. The primary exercises between video segments of this lesson are class-intensive simulation games in which members of the class 'infect' each other under alternative math modeling assumptions about disease progression. Also there is an occasional class discussion and local discussion with nearby classmates.

The topic of this video module is genetic basis for variation among humans. The main learning objective is that students will learn the genetic mechanisms that cause variation among humans (parents and children, brothers and sisters) and how to calculate the probability that two individuals will have an identical genetic makeup. This module does not require many prerequisites, only a general knowledge of DNA as the genetic material, as well as a knowledge of meiosis.