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In this interrupted case study, students meet a pair of fictional newlyweds on their way to Australia for their honeymoon. Initially eager to enjoy the sun, sand, and sights, Tanya and Julien Brahim end up more intimately acquainted with the local wildlife than they had planned. Tanya is bitten by a venomous arachnid and Julien has a run-in with a dangerous cnidarian. This case study was created to help students solidify their knowledge about cardiac myocytes, particularly ion movements associated with action potential generation in autorhythmic and contractile cells. As students work through the case, they will complete fill-in-the-blank paragraphs describing the heart, diagram membrane potentials and ion movements, and compare and contrast action potentials from different cell types. Written for a course in human physiology, the case requires some prior knowledge of membrane potentials, equilibrium potentials, ion gradients, neuronal action potentials, and skeletal muscle action potentials. An optional pre-case assignment (included in the teaching notes) can be used to make sure that students are familiar with the necessary concepts.

In this video Paul Andersen details the action potential in neurons. The resting potential of a neuron (-70mV) is maintained through differences in concentration and permeability of Na, K, and Cl ions. A graded potential is created as neurotransmitters from adjacent cells that are either excitatory or inhibitory. If the neuron reaches the threshold of -55mV an opening of voltage-gated sodium channels triggers an action potential

What do you and a sack of batteries have in common? Today, Hank explains. -- Table of Contents: Ion Channels Regulate Electrochemistry to Create Action Potential 4:51 Resting State 3:22 Depolarization 6:09 Repolarization 7:35 Hyperpolarization 8:00

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 presents the story of "Nick," a student who has been assigned the task of writing a research paper describing the fundamentals of chemical bonds and how they relate to human life. When Nick experiences difficulty remembering information about the different types of chemical bonds, he turns to his tutor, Josh, for help. Josh explains orbitals and valence electrons to Nick, and then they together review nonpolar and polar covalent bonds, ionic bonds, and hydrogen bonds. A final practical application exercise requires that students write about how different types of chemical bonds may relate to the development of Alzheimer's disease and to the mechanism of action of potential drug treatments.  The case is presented with PowerPoint slides and is designed to be used with a personal response system ("clickers"), but students can instead record their answers on paper or share them verbally.  The content is appropriate for use in high school and undergraduate introductory chemistry and biology courses.

This flipped clicker case study explores the fascinating relationship between the Arizona Bark Scorpion (the most venomous scorpion in North America) and the Southern Grasshopper Mouse. Initially it would seem that the grasshopper mouse is no match for the scorpion's venom; however, the grasshopper mouse is easily able to eat the scorpion and is largely immune to the scorpion's sting. By working through this case study, students learn about neuron anatomy and physiology as they explore how the grasshopper mouse is able to survive the scorpion's venom. This case study was developed for an introductory biology course for majors, but it could also be used in an introductory biology course for non-majors or in an anatomy and physiology course. The case requires that students learn basic neuron anatomy and action potential physiology prior to class by reading their textbook or by watching videos on the subjects. An optional set of guided questions tailored to Campbell Biology (10th ed.) is included in the teaching notes.