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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.

" IBM scientists have been able to differentiate the chemical bonds in individual molecules for the first time using a technique known as noncontact atomic force microscopy (AFM)."

Squirrels are frequent and beloved residents of college campuses throughout the United States, but oftentimes less welcomed by campus maintenance officials who report squirrels nesting in buildings, interfering with airflow from heating and cooling units, and destroying gutters. In this laboratory case, students act as members of a fictitious "squirrel task force" appointed by their campus administrators to provide recommendations for how to manage their school's squirrel population.  Students work in groups to assess the habitat suitability of their campus for squirrels by identifying and measuring trees that provide seasonal food for squirrels, and by identifying desirable hunting perches for common squirrel predators.  Students conduct squirrel surveys in designated campus zones to calculate the number of squirrels per acre on their campus and compare it with mean squirrel densities reported in forested areas and at a rival institution.  Students then compile and synthesize class data to provide management recommendations for university maintenance officials for either increasing or decreasing campus squirrel populations. Originally developed for an undergraduate wildlife biology course, the case could also be used in a lower-division biology or environmental studies course.

In this video Paul Andersen explains how the electrochemical gradient is a combination of the chemical and electrical gradient of ions. As ions move across a membrane the potential change creates a hidden force that isn't always apparent.

Chemist Daniel Nocera of Harvard University and his team joined forces with synthetic biologist Pamela Silver of Harvard Medical School and her team to craft a kind of living battery, which they call a bionic leaf for its melding of biology and technology. The device uses solar electricity from a photovoltaic panel to power the chemistry that splits water into oxygen and hydrogen.

What an incredible transformation. A protein used to help bones mend can also force pancreatic cells into producing insulin. The discovery could help people with type 1 diabetes produce their own insulin without having to take daily injections. In type 1 diabetes, beta cells in the pancreas that make insulin - the hormone that keeps our blood glucose levels at a safe concentration - are destroyed by the immune system. As a result, people with the disease have to inject themselves daily with insulin. Now, researchers have discovered that non-beta cells in the pancreas can be transformed into insulin-producing cells, merely by exposing them to a growth factor called BMP-7.

But now, a century and a half later, scientists from 11 different institutions have joined forces to amass all of that information, plus new data, to create the most comprehensive version of the tree so far. As detailed in a recent article in Proceedings of the National Academy of Sciences, the new Tree of Life shows how 2.3 million different types of animals, plants, fungi and microbes are interconnected, and how those relationships have diverged since life began on Earth more than 3.5 billion years ago.

Polar bears are an iconic symbol of climate change, but regionally relevant examples of susceptible biota are needed to highlight how global forces impact local environments. In this interrupted case study, students follow a young naturalist as she explores why saltmarsh sparrows are increasingly rare in coastal wetlands of the northeastern United States. In small groups, students diagram how sea-level rise may alter saltmarsh sparrow habitat and analyze a graph to determine if there is evidence to support sea-level rise. The social implications of rising sea levels induced by climate change can also be explored with an optional jigsaw activity. Students who successfully complete this case study will integrate key concepts related to sea level rise, interpret scientific data and draw conclusions about environmental change, and evaluate alternative management decisions. Originally developed for an undergraduate ecology course, the case could easily be adapted by college or high school instructors for an introductory biology or an environmental science course.

This clicker case addresses several concepts related to the evolutionary ecology of herbivore defenses. A survey of several different studies that investigated chemical defenses in Thymus vulgaris (thyme) gives students the opportunity to develop hypotheses, pose potential experiments, and interpret data to develop a better understanding of not only herbivore deterrence, but also how natural selection can involve different pressures selecting for different phenotypes. The case study incorporates group discussion, analysis of experimental design, and data evaluation as central activities. It can be taught in a single 50-minute class session, an economy that is achieved in part by using a "flipped" approach. Students prepare outside of class by watching several short videos (one of which was made by the author) that teach the basics of herbivore deterrence and abiotic and biotic forces in the environment that can influence plant adaptations. The case study was designed for use in a large introductory-level class, but would also be appropriate for smaller classes or upper-level evolution courses.

There are few areas of science more fiercely contested than the issue of what makes us who we are. Are we products of our environments or the embodiment of our genes? Is nature the governing force behind our behaviour or is it nurture? While almost everyone agrees that it's a mixture of both, there has been no end of disagreement about which is the dominant influence.

 is a web-based library of inquiry-based character-driven animated mysteries paired with differentiated supplemental activities that exposes students to the thrill of problem-solving. Mosa Mack allows educators to engage students while teaching standards-aligned content in a fun and engaging way while modeling scientific processing skills. Through its female protagonist whose passion for problem solving drives each story, Mosa Mack promotes diversity in the sciences while simultaneously providing teachers with an accessible way to incorporate inquiry into the classroom. Mosa Mack's unique inquiry-based approach targets the development of critical thinking skills for all students, with a particular focus on girls and minorities with historically low participation STEM fields.

North Carolina Science Now brings science out of the lab and into the classroom.  This collection of 5-7 minute videos includes related links and discussion questions for teachers and students.