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"This case study introduces students to Duchenne muscular dystrophy (DMD) and its underlying genetics, cell biology, and some of the associated biochemical pathways.  DMD is an X-linked disorder characterized by progressive muscle weakness and wasting due to the absence of a protein called dystrophin, which in turn causes degeneration of skeletal and cardiac muscle. There is currently no established cure for this disease.  The case follows the progress of "Casey," an undergraduate student who has just declared her biology major and is interested in expanding her scientific understanding of the different fields of biology. The case is organized in three parts: genetics, cell biology, and biochemistry, each exploring DMD through its unique lens. Throughout the case, Casey is presented with multiple outlets of information, including class lectures, direct e-mail interaction with a professor, scientific journals and websites, from which she (and any student engaged with the case) gathers knowledge about DMD."

Flinn Scientific has launched a website with an extensive amount of resources specifically developed to help teachers, students and parents continue their science education journey - even if that learning is taking place outside the classroom or laboratory environment. Examples of some of the resources we have developed: Free video labs with related teacher and student guides to help students at home continue making progress on key science topics More than 40 free, easy and fun-to-do activities that use commonly available materials to encourage science investigation in the home Flinn's unique digital learning solutions to facilitate seamless science learning. These online solutions are the perfect way to efficiently scale curriculum in an at-home setting - also free of charge On call scientists: over the coming days, we will be releasing video based lab experiments conducted by our scientific staff and broadcast from our studio with live events. As part of each live event, we will have our full team of scientists available to answer questions from teachers and students participating online - also free of charge and highly interactive and engaging. Be sure to check out our online calendar indicating the live schedule

Scientists have created an "artificial womb" in the hopes of someday using the device to save babies born extremely prematurely. So far the device has only been tested on fetal lambs. A study published Tuesday involving eight animals found the device appears effective at enabling very premature fetuses to develop normally for about a month.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome

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 following has been excerpted from a very popular Worthington publication which was originally published in 1972 as the Manual of Clinical Enzyme Measurements. While some of the presentation may seem somewhat dated, the basic concepts are still helpful for researchers who must use enzymes but who have little background in enzymology.

This directed case study was developed to introduce students to the CRISPR-Cas9 system for genome editing. CRISPR-Cas9 has made numerous headlines in both the scientific and popular press, and thus serves as an excellent model for learning current biotechnology and applying concepts from biology courses. After providing a general overview of CRISPR-Cas9, the majority of the case focuses on the clinical applications of the system as experienced by a carrier for the X-linked recessive allele underlying Duchenne Muscular Dystrophy. The case is structured so that students use a variety of popular and scientific sources (some of which may require a subscription to access-check with your institution), increasing in difficulty as they move through each part of the case. The goals are for students to learn the molecular mechanisms of CRISPR-Cas9, the benefits and limitations of the system, and the clinical applications of the technology. Open-ended questions are included to spark discussion of ethical considerations, societal impacts, and the overall implications of the technology.

This case study focuses on the intersection of defining a scientific species and defining a legal species. The compelling story of Lolita, an orca whale in captivity, is used to highlight the legal significance of species declaration. Students will work through scientific species definitions and data on Orca whales before deciding if Orca whales should be considered as one or several species. After an introduction to Lolita and a mock town hall meeting, students are thrown into the real life situation of contemplating the fate of an Orca in captivity that suddenly has protected legal status. This case was developed for use in a first-year biology course focusing on ecology, genetics, and evolution. It also could be used in upper or lower division courses on ecology, evolution, or conservation.

Almost 80% of all antibiotics in the United States aren't taken by people. They're given to cows, pigs, and chickens to make them grow more quickly or as a cheap alternative to keeping them healthy. These drugs could give rise to superbugs-bacteria that can't be treated with modern medicine-and things are only getting worse. In 2013, more than 131,000 tons of antibiotics were used in food animals worldwide; by 2030, it will be more than 200,000 tons. In a paper published today in Science, epidemiologist Thomas Van Boeckel of the Swiss Federal Institute of Technology in Zurich and colleagues outline the growing threat-and what can be done about it. Boeckel spoke to us about his team's work. This interview has been edited for clarity and length.

Topic: Surface Tension Why are drops spherical? Naahhh!!! It is because of surface tension. Surface tension is the property of liquids by which surface molecules of a liquid try to hold the liquid together by acquiring minimum surface area and acting like a stretched membrane. Alright!! I'll explain!! Inside a drop, each water molecule is pulled with a force by its neighboring molecules. As these forces are equal and opposite, they get neutralized. However, the molecule present at the surface is not attracted outwards. It is attracted only inwards and sideways. Sideways forces get neutralized. But because of the inward force, each surface molecule contracts to form a shape that has minimum surface area which is a sphere.

This case study describes a visit by "Naomi" to her physician, who upon seeing Naomi's bloodwork decides to prescribe her a cholesterol-lowering agent, a statin. The case discusses (1) the prevalence of non-communicable diseases such as atherosclerosis, which can lead to strokes and heart disease; (2) circulating lipoprotein particles including LDL and HDL, differentiating between which is a risk factor for heart disease and which is protective;  (3) the pathway for cholesterol synthesis; (4) the evidence demonstrating that statins inhibit the enzyme HMG-CoA reductase, which is the committed step for cholesterol synthesis; and (5) the kinetic mechanism by which statins inhibit the enzyme. Students examine and interpret data from radioactive tracer and enzyme kinetics studies. The case ends with another visit by Naomi to her physician, who reexamines her bloodwork after she has been taking a statin for six months. Students are asked to determine whether the drug was effective for Naomi and, if not, what changes could be made to her regimen. The case was originally written for use in a survey of biochemistry course for upper level undergraduates.

Currently there is considerable confusion surrounding the use of the term "organic" as applied to food and other consumer products, but within the agriculture industry the term has a well-defined meaning related to the practices that are allowed in the production of a crop. This case study was written to inform students about organic agriculture and its implications with regard to food nutritional value as well as its costs.  The case is presented as a dilemma in the context of buying produce in the grocery store. Concepts presented include the difference between organic and conventional agricultural practices, the analysis of food to quantify nutrient levels, the history of the organic movement, and the economic and environmental impacts of organic agriculture. The activity was designed for use in a lower level general science course (with a cursory review of the scientific literature) or in an upper level chemistry course (with a thorough analysis of the literature).

Tutoring Services has created a series of academic handouts to supplement the instruction content of Germanna courses.

The protagonist of this two-day flipped case study, "Maria," has two problems. She doesn't like it when the apple slices in her lunch turn brown, and she needs to find a project for her biology class that includes molecular biology, preferably one that incorporates plants. Students are enlisted to help Maria understand Arctic Apples™, which don't turn brown because they have been genetically modified to suppress the expression of polyphenol oxidase via RNAi. The case also explores the health, environmental, and safety aspects of growing and eating plants that have been genetically modified to use RNAi. The case applies the central dogma of biology to the creation of genetically modified foods and RNAi and includes a discussion of whether genetically modified foods should be labeled. Several videos are included with the case, including one created by the author specifically for the case. The case is appropriate for use in an introductory level biology or survey level biochemistry course.

This case study is designed to teach basic concepts of genetics by focusing on a rare disease, pseudoxanthoma elasticum (PXE).  Chromosome 16 is the narrator at the beginning of the case and introduces students to genes, chromosomes and mutations. The focus then shifts to the patient and his mother as she finds out about her son's disease and her subsequent efforts to connect with patient advocacy groups for support. The case concludes with students watching a TED talk given by Sharon Terry, the real-life mother on whom this story is loosely based, so that students can connect on an emotional and human level with someone who has intimate experience as a parent of children with a rare genetic disease. The case is suitable for high school general biology classes, but it can also be used by biology major or non-major undergraduates in a lower-division biology class, or in any lower-division non-major class focused on human disease.

Although rabies still causes thousands of deaths globally every year, it has essentially been eradicated from most industrialized countries. Part of the success story is due to an unusual project undertaken by the Swiss prompted by a series of large outbreaks in the 1970s: the large-scale vaccination of wild foxes to stop the epidemic. In this directed case study, students use an easily accessible MS Excel-based model to understand key epidemiological parameters of rabies outbreaks in wild foxes. The simple model allows students also to predict what proportion of foxes needs to be vaccinated to eradicate the virus from the population. The case fits into both ecological and microbiological (epidemiological) courses and offers opportunities to explore zoonotic diseases and "One Health" questions. The mathematical basis of the differential equations in the models is explained, although prior knowledge of calculus is not essential. A key learning outcome is the critical understanding of both the power and limitations of simple epidemiological models. This case was written for an online course but could also be used as a face-to-face activity if students have access to computers in class.

Say a red gummy bear has a baby with a yellow gummy bear - what percentage of red and yellow do the parents give to their children? Well, assuming gummy bear genetics works the same way we do, they'll have one set of chromosomes from their mum and one from their dad - so 50 percent from each - easy!

The alpha-gal-free pig has one express purpose for now: to develop medical products, like blood thinners, that won't set off adverse reactions.

In the broadest review on this topic that has been carried out to date, we found that, so far, 386 marine fish species are known to have ingested plastic debris, including 210 species that are commercially important. But findings of fish consuming plastic are on the rise. We speculate that this could be happening both because detection methods for microplastics are improving and because ocean plastic pollution continues to increase.

The data comes from the open Tree of Life Project, a collaboration among biologists and other scientists around the world. It contains decades' worth of work in phylogeny, evolutionary history of and relationships among groups of organisms. The project is about a year away from a complete tree of all life, Rosindell said. He wanted a system in place that could visualize it as soon as it's ready. Right now, OneZoom only contains mammals, but that's still more than 5,000 species, all correlated with each other and color-coded according to their threat levels. Rosindell has big plans for the rest, and he even wants to build a searchable app for smartphones, showcasing the history and relationships between all life on Earth.