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his resource describes an inquiry-based, in-class exercise designed for students working in small groups. It is designed to review and enrich student understanding of probability, how probabilities of individual events can be combined to make predictions about more complex outcomes, and how observed data can be compared to a null model based on probabilities using a chi-squared test. These skills are used extensively for classical genetic analysis. Throughout the activity, peers and instructors guide students through the process of developing and solving problems using probabilities and chi-squared tests in small groups.

This activity guides the analysis of a published scientific figure from a study that modeled the impact of an infectious fungal disease on a bat population. In 2006, a disease called white-nose syndrome (WNS) began wiping out bat populations in North America. Because many of these bats eat insect pests, the spread of WNS may devastate ecosystems and increase pest control costs. In this study, scientists mathematically modeled the effects of WNS to estimate extinction probabilities for the little brown bat (Myotis lucifugus) population in the northeastern United States. This figure shows these probabilities projected for five annual rates of population decline. Each projection is simulated up to 100 years after WNS emerged in the population. The "Educator Materials" document includes a captioned figure, background information, graph interpretation, and discussion questions. The "Student Handout" includes a captioned figure and background information.

4:42 At least one entire class of dinosaurs seems to have had feathers -- including velociraptors, and probably T. rex. Find out how we know, and how we even know what color some of them were!

Sure, we know insufficient serotonin levels get a bad rap when it comes to depression, but that's like blaming one person in a full-scale riot. Depression isn't caused by only one factor. In fact, study co-author Elyse Aurbach says we're probably not getting to the core of why people are depressed because "the brain is immensely complex." In this study, the research team conducted eight experiments (four on animal brains, four on brains of the deceased human kind) of varying sample sizes - from 20 to 90 brains in each - and found that the brains of deceased humans who'd been depressed had increased levels of hippocampal FGF9 and that live animals with increased FGF9 levels demonstrated depressive, anxious behavior. "This is not just a correlation," study leader Huda Akil of the University of Michigan says. Less really may be more, at least when it comes to FGF9.

Humans construct boundaries -- around our homes, our neighborhoods, and our nations -- to bring order to a chaotic world. But we rarely consider how these boundaries affect other creatures. In this episode of Think Like A Scientist, we meet conservation photographer Krista Schlyer, who has spent the last seven years documenting the environmental effects of the U.S./Mexico border wall, and biologist Jon Beckmann, who studies how man-made barriers influence the movement of wildlife. Schlyer and Beckmann have seen damaging impacts of the border wall firsthand, but they remain optimistic. Humans probably won't stop constructing walls and fences any time soon, but planning our boundaries with wildlife in mind can help prevent these structures from causing environmental harm.

Ah, spring. Grass growing, flowers blooming, trees budding. For those with allergies, though, this explosion of new life probably inspires more dread than joy. So what's behind this annual onslaught of mucus? Eleanor Nelsen explains what happens when your immune system goes rogue.

Many of these labs allow students to test multiple variables. Caution: the journal and data entry sections of the simulations do not work, so you probably will want to arrange for students to write these on their own pages. Many of these labs are useful to substitute for activities in the class that are too costly, dangerous, or time consuming. I have assigned grades to some that I've explored in detail. Grades are based on interactivity, useability, and overall value of the exploration. Many of these can be used as simple class demonstrations, whereas others are more useful for having students explore and change variables.

Hank talks about chimeras, and why Venus the cat probably isn't one - but your mom might be!

DNA from a man who lived in Ethiopia about 4,500 years ago is prompting scientists to rethink the history of human migration in Africa. Until now, the conventional wisdom had been that the first groups of modern humans left Africa roughly 70,000 years ago, stopping in the Middle East en route to Europe, Asia and beyond. Then about 3,000 years ago, a group of farmers from the Middle East and present-day Turkey came back to the Horn of Africa (probably bringing crops like wheat, barley and lentils with them).

The activity of some of our genes varies with the seasons throughout the year. The discovery comes from an analysis of blood samples from more than 16,000 people in both hemispheres. The most striking pattern was that 147 genes involved in the immune system made it more reactive or "pro-inflammatory" during winter or rainy seasons, probably to battle the onslaught of cold and flu viruses

You're probably aware of eight basic blood types: A, AB, B and O, each of which can be "positive" or "negative." They're the most important, because a patient who receives ABO +/- incompatible blood very often experiences a dangerous immune reaction. For the sake of simplicity, these are the types that organizations like the Red Cross usually talk about. But this system turns out to be a big oversimplification. Each of these eight types of blood can be subdivided into many distinct varieties. There are millions in all, each classified according to the little markers called antigens that coat the surface of red blood cells.

If thinking about the billions of bacteria taking up residence in and on your body gives you the willies, you probably won't find it comforting that humans are also full of viruses. These maligned microbes are actually intertwined in the very fibers of our being-about 8 percent of our genetic material is made up of absorbed forms of retroviruses, the viral family to which HIV, the pathogen that causes AIDS, belongs.

Pheidole dentata, a native of the southeastern U.S., isn't immortal. But scientists have found that it doesn't seem to show any signs of aging. Old worker ants can take care of infants, forage and attack prey just as well as the youngsters, and their brains appear just as sharp. "We really get a picture that these ants-throughout much of the lifespan that we measured, which is probably longer than the lifespan under natural conditions-really don't decline," says Ysabel Giraldo, who studied the ants for her doctoral thesis at Boston University.

You have probably had the burning sensation of eating a jalapeno or other tear-inducing pepper. What causes this painful fire in your mouth? The short answer is capsaicin. But what exactly is capsaicin? How does it work? Why do people drink milk to relieve the pain? Reactions has the chemistry to answer all of these sizzling questions.

Early classification systems probably grouped organisms as to whether they were beneficial or harmful. Another ancient classification system recognized 5 animal groups - domestic animals, wild animals, creeping animals, flying animals, and sea animals.

I'm sure you've probably heard of at least a few invasive species. Maybe you've heard of the Cane Toad. It's one of the classic introductions of invasive species gone wrong. It was introduced to eat pests in cane fields and then turned into a plague of epic proportions in Northern Australia. But here is the question. Now that these species are here, is it worth fighting their spread, or should we spend time and effort on other things. It's worth asking, and not just for the ethical implications. We live in a modern world and I think there is a real financial element to this as well. See if you can follow my logic through this video short. Do you agree with my thoughts? Should we keep fighting? Do you have any personal experience with an invasive species?

In this case study, students will have the opportunity to model the spread of tuberculosis and development of antibiotic resistance in a hypothetical prison environment. After reading a brief handout and viewing a short video, students play a simulation game by first identifying a group of prison inmates represented by index cards. The placement of the cards will influence how drug resistance spreads from one inmate to another. Using a dice roll to mimic random probability of infection and antibiotic misuse, students then track the development of resistance to four specific antibiotics, determined by selection of playing card suit. Opportunity for release or transfer on inmates from one facility to another introduces a further level of complexity, allowing students to study resistance spread. This activity was originally designed for a section of an upper-division biology course about antibiotic resistance, but it would also be appropriate for lower-division undergraduate and high school biology courses discussing antibiotic use.

This PowerPoint-driven, flipped case study begins with a short video about a woman suffering from cystic fibrosis (CF) in the 1970s, a friend of the lead author's, whom she met in college and who died in her twenties. Hooked by this personal story, students then delve into the genetics and biology of cystic fibrosis as they learn about the difference between dominant and recessive genes, make Punnett squares that depict various types of inheritance, distinguish between probability and actual numbers, differentiate types of mutations, and learn about the opportunistic infections that CF patients often succumb to.  Students conclude the case by watching two additional videos on chest compression machines and the contemporary life expectancy of patients with CF.  In addition to the scientific content presented in the case, it is hoped that students will empathize with, and be motivated by, the young people presented in the videos as they struggle with a very real, incurable disease deeply rooted in genetics.

The resource covers basic logic and faulty arguments, developing student's critical thinking skills. Suitable for year 8-10, focused on science issues, the module can be adapted to suit classroom plans.

TinkerPlots is a data visualization and modeling tool developed for use by middle school through university students. TinkerPlots can be used to teach grades 4 and up in subjects including math, statistics, social science, or physical or biological science

TinkerPlots is a data visualization and modeling tool developed for use by middle school through university students. TinkerPlots can be used to teach grades 4 and up in subjects including math, statistics, social science, or physical or biological science