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This interrupted case study introduces the topic of bacterial sporulation and cannibalism in Bacillus subtilis. The storyline follows Susan and her lab mates who are presenting research at a lab meeting when Susan falls asleep and dreams they are stranded on a deserted island. She makes connections between their fight for survival in the dream and the survival mechanisms of the bacteria they study in the lab. The benefits of sporulation under conditions of sustained stress are fairly obvious, but Susan's dream is used to examine the idea that sporulation may not always be beneficial and that bacteria would not want to commit to entering such a state in response to temporary stresses. Through the analysis of actual data from the scientific literature, students uncover a mechanism by which B. subtilis delays its commitment to sporulation by killing members of its own species to release nutrients (i.e., cannibalism). Originally developed for a general undergraduate microbiology course when discussing the structure and growth of prokaryotic cells, the case could also be used in an introductory biology course that emphasizes bacteria and data literacy.

This flipped case study explores how the topics of membrane structure, transport, and signaling via membrane-bound receptors are intimately associated with the paralysis of muscle targeted by botulinum neurotoxin. The case scenario revolves around a fictitious socialite that has requested the assistance of her personal concierge physician with a condition that has developed after having participated in a Hamptons Botox party. The physician and a shadowing pre-med undergraduate chat about the molecular mechanisms behind Botox induced muscle paralysis. The case is designed as an engaging capstone exercise for students to gain appreciation for how knowledge of basic cellular and molecular biology mechanisms are essential for pharmaceutical development and medical patient diagnosis and prognosis. Written for an undergraduate general biology course, the case is also suitable for use in courses such as cellular biology, neurobiology, or human physiology.

This clicker case was designed to teach students about basic enzyme structure, mechanisms of enzyme inhibition, and mechanisms of drug resistance. The story follows Oliver Casey, a patient afflicted with Chronic Myelogenous Leukemia (CML). CML is caused by a chromosomal mutation that affects the tyrosine kinase ABL, an enzyme important in regulating cell growth and proliferation. The chromosomal mutation gives rise to the BCR-ABL fusion gene that produces a constitutively active ABL kinase, which causes the leukemia. In May 2001, the Food and Drug Administration approved the use of a rationally designed tyrosine kinase inhibitor, imatinib (Gleevec®), for the treatment of CML. During that same month, Gleevec made the cover of TIME magazine, described as "new ammunition in the war on cancer." The case is structured for a flipped classroom environment in which students view preparatory videos (including one by the author) on their own before beginning the case. Written for a first-year introductory biology course, the case could also be adapted for AP/Honors high school biology or a cancer biology course.

"Biologists at the University of Rochester have determined how blind mole rats fight off cancer -- and the mechanism differs from what they discovered three years ago in another long-lived and cancer-resistant mole rat species, the naked mole rat."

Four talks focus on sex determination-the molecular and genetic mechanisms that determine whether an organism will be male, female or a hermaphrodite.

Four talks focus on sex determination-the molecular and genetic mechanisms that determine whether an organism will be male, female or a hermaphrodite. Meisosis animation 49:00-53:00 53:21 SRY animation Y to X crossing over 53:30 SRY transfer 54:45

Taylor must write a report about a natural toxin while she is home from college on break. After a family dinner conversation about the latest attempt to poison a politician via a letter, Taylor decides to explore how ricin acts as a poison. Students work in small groups to help Taylor by working through figures from primary literature papers and exploring the use of an in vitro translation system, sucrose gradient fractionation and the effect of inhibiting various steps of translation.  A shorter, second day activity involves students looking further at the effect of ricin upon ribosome function and at the ricin protein itself.  Students individually complete a cumulative assignment of writing a letter back to Mom and Dad about how ricin has its effects. This case was designed for use in a second semester biochemistry course or a molecular biology course that incorporates the mechanism of transcription. Prerequisite knowledge includes a general understanding of the steps of translation and the ability to interpret data from agarose gels.

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

This clicker case study follows a dialogue between two college students, Lucy and Dan, as they discover how alternative splicing of mRNA molecules can allow a single gene to code for multiple proteins. Dan is participating in a clinical trial for a drug that may treat his migraines by inhibiting calcitonin gene-related peptide, and Lucy is working in a summer research lab that studies the protein calcitonin. They soon realize that the two proteins are both encoded by the same gene, and through their questioning and dialogue they come to understand the phenomenon of alternative splicing. They also learn about other steps of mRNA processing and about monoclonal antibodies. This case was designed to be taught in a flipped classroom, but could easily be adapted for a more traditional classroom setting if content covered in the pre-class videos is covered during the case study instead. It was designed for an introductory-level molecular biology course, but could be adapted for higher levels by including more information about the physiology and regulatory mechanisms involved.

This case study explores the recent (2010 - 2016) outbreak of neural tube defects, specifically anencephaly, in a rural three-county region of Washington state, particularly Yakima, WA. The case study focuses on the biological aspects of teratogens that may cause birth defects as well as epidemiological investigations of disease outbreaks. By the end of the case, students will have explored how our environment may have severe biological consequences on the human body during pregnancy and will have evaluated governmental and scientific investigations of a rare outbreak of birth defects. This clicker case study was developed for a non-majors biology course entitled "Human Development: Conception to Birth," although it could be taught in any introductory biology course for majors or non-majors during a unit on human reproductive biology or developmental biology. The case assumes that students have no prior knowledge of developmental biology or birth defects. The case study could also be adapted for upper-division courses by getting more in-depth on the specifics of teratogen mechanisms, the developmental biology and physiology of neural tube defects, or more complex epidemiological analyses.

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

Signaling at the neuromuscular junction (NMJ) is a complex process that is required for many actions that sustain life within humans. Toxins that act upon the NMJ, both natural and synthetic, act in a variety of ways to inhibit this function. This case study examines how a variety of toxins can act to disrupt the normal mechanism of function of the NMJ  by placing a protagonist ("Unlucky Chucky") at an eco-spa in Colombia with his good friend Melody. Unfortunately, during their time at the eco-spa, things don't always turn out well for Chucky. A variety of neuromuscular toxins are discussed including curare (d-tubocurarine), Botox (botulinum toxin A), physostigmine and sarin gas (GB). This case was designed to be used in a variety of classrooms ranging from an undergraduate introduction to biology course in a module focused on neuromuscular functioning, to an introduction to physiology course as an introduction to the NMJ; it could also potentially be used in a nursing course that is examining NMJ physiology.

This case study is centered on a real scenario from 2013 in which the Kickstarter fundraising platform included a fundraising proposal from a group wanting to use synthetic biology to make glowing plants. The proposal raised controversy because the Glowing Plant group offered to give away their genetically-modified glowing plant product to investors.  Kickstarter subsequently changed its policy to prevent use of genetically modified organisms as rewards or incentives to investors. This case study was developed for a college first-year seminar focused on the ethics of synthetic biology, and was introduced during the first week of the semester. The case uses the jigsaw teaching method to introduce students both to the mechanics of synthetic biology and to questions about how we should distribute the benefits and burdens associated with new or emerging technologies. It could be adapted for courses in introductory college biology, genetics or bioethics.

Common in cuisine all around the globe, onions are renowned for their ability to make us all look like cry babies. In Reactions' latest video, we get to the bottom of this teary phenomenon and reveal exactly what chemical mechanisms trigger it. The video also features a few chemistry-backed tips you can try at home to stop the tears before they start.

This case study was inspired by a real-life scenario, and follows the story of Roberto, a migrant farmworker whose health is impacted by the usage of pesticides on a farm.  With the help of a health care provider, Roberto becomes aware of the effects of pesticides on his well-being. Students utilize a database and draw conclusions from data in order to answer the case questions.  The case concludes with an activity that uses the "intimate debate" technique in which students use scientific data as evidence to argue whether or not the pesticide under discussion should be banned from usage.  This case was originally developed for undergraduate anatomy and physiology or toxicology courses. Students are expected to have some background knowledge in nerve structure and function as well as the mechanics of neural transmission before starting the case.

This case study follows a young cystic fibrosis (CF) patient named Lucas. Through Lucas's story and interactions between his parents and pediatrician, students learn about the scientific background and basis of CF. By reviewing email correspondence between Lucas's parents and various doctors, students gain an overview of CF research. CF has become a model disease in certain undergraduate biology classrooms due to its relatively clear mechanism and genetic basis. This case asks students to come up with their own ideas to improve on an existing line of research - gene therapy - in treating CF. During the process, students will gain a better appreciation of the innovative nature of science and develop research skills such as finding, understanding and analyzing primary literature. The activity was originally designed for first- and second-year students as part of an extracurricular case competition, but may be used for any undergraduate biology level. The case assumes basic (high school level) knowledge of genetics, biochemistry, cell biology and physiology.

2:51 minute video about mechanics of transcription and translation 

5:35 minute video on ATP hydrolysis

The structure of DNA, discovered by James Watson and Francis Crick, suggests a mechanism of replication. The double helix unwinds, and each strand acts as a template for the construction of the new DNA molecule.

Quick look: In its modern sense, epigenetics is the term used to describe inheritance by mechanisms other than through the DNA sequence of genes. It can apply to characteristics passed from a cell to its daughter cells in cell division and to traits of a whole organism. It works through chemical tags added to chromosomes that in effect switch genes on or off.

"CRACKING THE CODE"/"Cloning Paper Plasmid" activities can (1) serve as a review of the "genetic code" and the role it plays in our life; and, (2) to help students see how genes may be manipulated for genetic research, namely, gene cloning/genetic engineering. The laboratory time, the specialized equipment and expertise to carry out recombinant DNA experiments may be lacking in the high school. Activity 2 will help students conceptualize the mechanics involved in cutting and ligating DNAs into a plasmid vector with "sticky ends" of complementary DNA base pairs.