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A team of Indian biologists has demonstrated that a key component of the water buffalo genome can be manipulated to produce foreign proteins in the buffalo's milk (J. Biotechnol. 2015, DOI:10.1016/j.jbiotec.2015.02.001). The findings suggest the possibility of modifying the genetic material of water buffalo-that is, creating transgenic buffalo-to produce protein drugs, says team member Subeer S. Majumdar, of the National Institute of Immunology, in New Delhi.

When an elementary school teacher calls in sick to work, she finds out that she is not the only one who will be missing school that day.  Children from her fifth grade class have also become ill and parents are calling to report the absences. The concerned principal of the school finds out the fifth grade class had a field trip to one of the local parks the day before. The case shows the areas visited by the class and provides discussion between the principal and a physician that teaches the readers about water quality and EPA standards for bacteria levels in recreational water. The case has an optional lab component that provides the theory for three methods that can be used to conduct microbial water analyses.  Procedures are included for teachers to lead a lab activity to test water to identify which location in the park caused the illness. This case study and accompanying laboratory activity are recommended for an environmental engineering course or a lower level science course.

This case study is used to teach undergraduate students about hydraulic fracturing (hydrofracking), a controversial method for extracting methane from shale. The controversy arises from claims that chemicals used in the fracking process and the methane itself find their way into drinking water and are also sometimes found at dangerous levels in the air. The case study begins in a college chemistry class where a student inquires about a news item he saw about residents setting their tap water on fire. The instructor uses this as an opportunity for the students to research hydrofracking and natural gas, and she then integrate these topics into their present study of isotopes. The class first examines what isotopes are by using a guided inquiry based activity. The students then learn how mass spectrometry, which uses the principles just learned about isotopes, is employed to determine the source of methane in contaminated wells. This case study is designed for freshman chemistry students and students in environmental studies.

This case study presents a realistic example of drinking water contamination within a fictional local community and leads students through an abbreviated human health risk assessment. Students are provided background information about the extent of the contamination and a description of the contaminated site and are then required to calculate both the cancer and non-cancer risks to the community. This exercise is appropriate for an environmental toxicology or environmental risk assessment course. It works well after a lecture on the basics of risk assessment including how to calculate exposure intakes and risk estimates.

This case study centers on an active teaching game that simulates a cholera outbreak among five villages along a river, similar to the Haitian outbreak of 2010. By enacting the behaviors of fictional villagers, students learn how trade, travel, sanitation practices and geographic location contribute to the spread of diarrheal disease. Documenting various contamination events of village water supplies allows students to trace the progression of the disease and illustrates how adequate sanitation facilities provide protection against the bacteria Vibrio cholera. Originally designed for an undergraduate upper-division biology course focusing on the epidemiology of diseases, the simulation is also appropriate for microbiology and public health courses, as well as lower division undergraduate biology courses and high school. Biology or epidemiology components of the case study can be highlighted depending on the emphasis of the course being taught. The game can be completed within a 45- to 60-minute class period. Playing cards are available from the Supplemental Materials tab; detailed instructions are found in the teaching notes.

This directed case study examines the molecular basis of cystic fibrosis to emphasize the relationship between the genetic code stored in a DNA sequence and the encoded protein's structure and function. Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein that functions to help maintain salt and water balance along the surface of the lung and gastrointestinal tract. This case introduces students to "Maggie," who has just been diagnosed with cystic fibrosis. The students must identify the mutation causing Maggie's disease by transcribing and translating a portion of the wildtype and mutated CFTR gene. Students then compare the three-dimensional structures of the resulting proteins to better understand the effect a single amino acid mutation can have on the overall shape of a protein. Students also review the concepts of tonicity and osmosis to examine how the defective CFTR protein leads to an increase in the viscosity of mucus in cystic fibrosis patients. This case was developed for use in an introductory college-level biology course but could also be adapted for use in an upper-level cell or molecular biology course.

Loss of species richness is often due to anthropogenic activity. The global decline of amphibians is one such example. This case study examines the impact of road deicing agents on amphibians living near bridges and roads treated heavily with salt during the winter months. Concepts explored in this case include changes to the aquatic environment as a result of road deicing applications, bioaccumulation, osmoregulation in amphibians living in clean freshwater, and the impact of increased aquatic salinity levels on the ability of amphibians to adequately osmoregulate in an environment for which they are not adapted. Three short videos created by the author can be shown in class or assigned for viewing in advance for a "flipped" classroom approach. Originally developed for a general education/introductory biology course, the case could also be used with introductory level animal anatomy and physiology courses as part of a deeper exploration of the renal system.