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New research shows our DNA is absolutely loaded with... NOTHING. 98 percent of our DNA plays no role in our development. But as Trace learns, the findings may not be so black and white.

This flipped case study tells the story of Joyce, a biology student who notices the development of some unusual symptoms (foot slapping and slurred speech) in her mother. In an effort to understand the cause, Joyce views a documentary-style trigger video (created by the case author) that suggests to Joyce that her mom may in fact have amyotrophic lateral sclerosis or ALS. The rest of the case walks Joyce through understanding how normal neurons compare to neurons in ALS patients and how that might affect muscle function. The case explores the link between genes, particularly SOD-1, to the formation of malformed proteins and its potential role in the development of ALS. The case concludes with a discussion of drug development and highlights the timeline and costs associated with drug discovery as Joyce becomes concerned about the lack of drugs in the pipeline for ALS, which her mother is ultimately diagnosed with. The case is appropriate for a number of classes including general biology, biotechnology, anatomy and physiology, upper level-cell biology, or any human health and disease-related course.

The theory of evolution by natural selection is simple, elegant, and profound. Yet, a large number of undergraduate students including biology majors, medical students, and pre-service science teachers maintain a large set of misconceptions that interfere with a solid understanding of the process of natural selection. It is also well known that lecturing is an insufficient strategy to help students confront and correct these misconceptions. This activity uses the evolution of coat color in oldfield mice (Peromyscus polionotus) as the basis of a case study in which students investigate the role of variation, heritability, and selection in the evolution of a trait. Students examine graphs, data, and excerpts from a series of papers that have been published about this system over the last 100 years. The content is delivered as an interrupted case and encourages peer-to-peer teaching and interaction. The case is appropriate for use in non-major, introductory, or advanced biology courses.

This interdisciplinary case study uses the format of a progressive disclosure to explore certain advances in biotechnology and evaluate them within the framework of societal needs, concerns and pressures.  When faced with a heart valve transplant, a high school student and her mother must decide between multiple approaches, some current and others emergent. Highlighted in this case study are the topics of xenotransplantation, 3D bioprinting and the mature minor rule. The case includes a role-playing, public hearing activity that can be used to explore many aspects at the interface of technology and culture: religious rights, parental rights, public health care policy and safety, animal rights, economic issues of organ marketing, and psychological issues of body image.  This case study was originally designed for first year collegiate classes (introduction to biology, introduction to psychology) but is also applicable to AP high school. The flexible nature of the case also allows for expansion of several aspects for advanced classes across multiple disciplines.

This case study uses a jigsaw activity to introduce students to four specific plant responses to climate change: elevational range shifts, phenology shifts, community shifts, and changes in biodiversity. Students become "experts" on one of these responses by reading an article (from Nature, Science, or American Journal of Botany; not included with the case) on their assigned topic and then sharing their expertise with others in class. In order to hone their understanding and increase retention on these topics, students then learn about plant communities found in a specific system-vernal pools or seasonal wetlands typical of Mediterranean climates (a PowerPoint presentation on this topic is included). Students accomplish several small group tasks to assess how different vernal pool plant communities have responded to fluctuations in annual weather patterns and predict how these communities may respond to greater weather variability resulting from future climatic change. This case was written for mid- to upper-level ecology, plant ecology, botany, or environmental studies courses. The material covered may also be suitable for classes examining the role of weather variability/climate change in relation to plants.

This directed case study follows the story of "Pauline," a 20-year-old college student who has just received results from a personal genetic testing kit she purchased online. The report shows a negative result for variants of the BRCA 1 and 2 genes, which are associated with a greater risk for breast cancer. Although Pauline has a family history of breast cancer, she concludes that she no longer needs to be concerned, or does she? As students work through the questions in this case study, they review the role of genes and how they code for proteins as well as the effects of proteins on health, especially on cellular growth regulation and cancer. They also learn about the process of genetic testing and consider the ramifications of positive and negative tests for diseases or health conditions, especially with respect to breast cancer. The case is designed for non-science majors in a scientific methods course and could also be used in an introductory biology course. The questions in the case could be adapted for an upper level genetics class.

A common misconception is that Darwin suggested that something as complex as the eye could not have evolved through natural selection. While the misunderstanding often comes from an incomplete reading of his argument, we have long known that intermediate varieties of eyes (e.g., eyespots, cupped eyes, and complex camera-type eyes) exist in a variety of organisms. Eyes are so common that it was thought that they had evolved independently 40-60 times. More recent molecular work, however, has identified the role of Pax6 genes and their homologs in the formation of eyes during development. The basic information for eye formation appears to have been present in the common ancestor to all bilaterans, and perhaps may be more ancient than that. This interrupted case study examines the history of evidence for eye evolution from Darwin's initial postulates, through evidence of multiple intermediate forms, concluding in an examination of Pax6 homologs. The case is primarily for an introductory biology class but an additional section would be appropriate for upper-level evolution or developmental biology courses.

The life science/biology course is divided into 12 instructional segments grouped into four sections. In the first section, From Molecules to Organisms: Structures and Processes, students develop models of how molecules combine to build cells and organisms (IS1 [Structure and Function]; IS2 [Growth and Development of Organisms]; IS3 [Organization for Matter and Energy Flow in Organisms]). In the second section, Ecosystems: Interactions, Energy, and Dynamics, students zoom out to the macroscopic scale to show how organisms interact (IS4 [Interdependent Relationships in Ecosystems]; IS5 [Cycles of Matter and Energy Transfer in Ecosystems]; IS6 [Ecosystem Dynamics, Functioning, and Resilience]; IS7 [Social Interactions and Group Behavior]). Students return to the role that DNA plays in inheritance during the third section, Heredity: Inheritance and Variation of Traits (IS8 [Inheritance of Traits]; IS9 [Variation of Traits]). The class ends tying together interactions at all these scales by explaining evolution and natural selection in Biological Evolution: Unity and Diversity (IS10 [Evidence of Common Ancestry and Diversity]; IS11 [Natural Selection]; IS12 [Adaptation and Biodiversity]). A vignette in IS12 illustrates the level of three-dimensional understanding students are expected to exhibit as a capstone of the course.

In this project, students will be asked to actually measure the amount of waste that they generate in a week's time (identifying single-use plastic or not) and devise creative ways in which the can reduce, reuse and/or recycle to take an active role in their environment.

This activity complements the video Virus Hunter: Monitoring Nipah Virus in Bat Populations. Students explore cases of Nipah virus infection, analyze evidence, and make calculations and predictions based on data. Students assume the role of epidemiologists analyzing real data from an outbreak of Nipah virus in Malaysia, attempting to identify the reservoir of the virus and curtail the outbreak. Students will make predictions, perform calculations, adapt to new information, and make recommendations to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO).

The behavior of a person's genes doesn't just depend on the genes' DNA sequence - it's also affected by so-called epigenetic factors. Changes in these factors can play a critical role in disease.

Although genetic factors contribute to congenital heart disease, many children born with heart defects have healthy parents and siblings, suggesting that new mutations that arise spontaneously -- known as de novo mutations -- might contribute to the disease. New research shows that about 10 percent of these defects are caused by genetic mutations that are absent in the parents of affected children.