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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).

The life science/biology course is divided into 12 instructional segments grouped into four sections. In the first section, From Molecules to Organisms: Structures and Processes, students develop models of how molecules combine to build cells and organisms (IS1 [Structure and Function]; IS2 [Growth and Development of Organisms]; IS3 [Organization for Matter and Energy Flow in Organisms]). In the second section, Ecosystems: Interactions, Energy, and Dynamics, students zoom out to the macroscopic scale to show how organisms interact (IS4 [Interdependent Relationships in Ecosystems]; IS5 [Cycles of Matter and Energy Transfer in Ecosystems]; IS6 [Ecosystem Dynamics, Functioning, and Resilience]; IS7 [Social Interactions and Group Behavior]). Students return to the role that DNA plays in inheritance during the third section, Heredity: Inheritance and Variation of Traits (IS8 [Inheritance of Traits]; IS9 [Variation of Traits]). The class ends tying together interactions at all these scales by explaining evolution and natural selection in Biological Evolution: Unity and Diversity (IS10 [Evidence of Common Ancestry and Diversity]; IS11 [Natural Selection]; IS12 [Adaptation and Biodiversity]). A vignette in IS12 illustrates the level of three-dimensional understanding students are expected to exhibit as a capstone of the course.

Some thyroid 101 background: Your thyroid gland is the butterfly-shaped gland at the base of your neck that secretes two all-important hormones that control major bodily functions (including how you use energy, regulate body temperature, and digest food) and organs (including the heart, brain, liver, kidneys and skin). But with hypothyroidism, your body can have normal to low thyroxine hormone levels and elevated thyroid stimulating hormone (TSH) levels. These high TSH levels are a result of an overworked pituitary gland that is trying to elevate the hormone levels in an inadequately responsive thyroid.

This case study follows two beginning undergraduate researchers on a quest for a summer research project related to food web ecology. While writing their research proposal, the students receive feedback indicating that they have neglected an entire group of organisms from their food web-parasites, which leads them to a scientific research paper discussing how these organisms have been overlooked by scientists studying food webs, the challenges involved with including parasites in food webs, and the contributions parasites ultimately make to food webs. An integrated activity in which students visualize the food web using images of organisms and answer questions about species interactions provides opportunities to examine key concepts such as omnivory, ontogenetic diet changes, trophic levels, complex life cycles, and taxonomic aggregation. This case study was originally written for an undergraduate general ecology course, but could easily be adapted to undergraduate general biology courses covering community ecology or specific courses in invertebrate zoology, parasitology, or disease ecology. The teaching notes also discuss how the included code for R statistical computing software can be used to extend the case study in a more quantitative direction if desired.

Nitrogen is one of the primary nutrients critical for the survival of all living organisms. Although nitrogen is very abundant in the atmosphere, it is largely inaccessible in this form to most organisms. This article explores how nitrogen becomes available to organisms and what changes in nitrogen levels as a result of human activity means to local and global ecosystems.

Genomics resources for teachers, from state of Michigan. This website includes three main sections: Family History- which looks into genomics at the organism level Multifactorial Traits- which looks into genomics at the cellular and gene level Genetic Variation- which looks into genomics at the molecular level

The Amoeba Sisters tour through the biological levels of organization starting with cells and ending with the biosphere!

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.

After her two children were diagnosed with a rare genetic condition, Sharon Terry dedicated her life to creating systems-level solutions that will alleviate burdens for consumers and build opportunities for them to be empowered in their own health care. She is the CEO of Genetic Alliance, an international non-profit organization, now in its 25th year, that is the world's largest network of health related organizations working from a consumer perspective. Genetic Alliance builds capacity within the genetics and health community by forging novel partnerships, promoting informed decision-making, and sharing individual, family, and community perspectives.

4:17 video Think of the ozone layer as Earth's sunglasses, protecting life on the surface from the harmful glare of the sun's strongest ultraviolet rays, which can cause skin cancer and other maladies. Ozone stinks. People who breathe it gag as their lungs burn. The EPA classifies ground-level ozone as air pollution. Yet without it, life on Earth would be impossible. A fragile layer of ozone 25 km above Earth's surface is all that stands between us and some of the harshest UV rays from the sun. The ozone molecule O3 blocks radiation which would otherwise burn skin and cause cancer. On Mars, which has no ozone layer to protect it, solar UV rays strafe the surface with deadly effect, leaving the apparently lifeless planet without the simplest of organic molecules in the upper millimeters of exposed Martian soil.

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.

Scientists and healthcare professionals initially exhibited little concern over the Zika virus even after evidence of human infection was first identified in 1952; Zika appeared to be both rare and unassociated with morbidity or mortality. Around 2015 all of this changed as journalists, scientists, public health officials, and laypeople scrambled to learn about its varied modes of transmission and devastating consequences (e.g., birth defects and autoimmune disorders). Although research continues to rapidly evolve, this case study directs students to reliable scientific sources (e.g., Centers for Disease Control and World Health Organization) that will likely continue to provide the most current information in order to explore questions such as: Where did the virus come from? How does it spread? What can we do to prevent it? Students will also consider the public health challenges and possible solutions associated with emerging infectious diseases. The case was originally written for an upper-level biology or public health course in which students already have some basic background knowledge regarding viruses, vaccines, and infectious disease.

Every year, it inflicts between 250,000 and 500,000 helpless and malnourished young people with early-life blindness. And in half of those cases, it also brings death, according to the World Health Organization. Vitamin A deficiency also puts pregnant women at risk. It's rare in developed countries, but the goal of completely eradicating vitamin A deficiency - mostly in Africa and Southeast Asia - remains unmet. Scientists are now working to genetically engineer "super" bananas that are fortified with crucial alpha- and beta-carotene, which the body converts to vitamin A.

When you look at yourself in the mirror you may ask, 'How, given that all the cells in my body carry the same DNA, can my organs look so unlike and function so differently?' With the recent progress in epigenetics, we are beginning to understand. We now know that cells use their genetic material in different ways: genes are switched on and off, resulting in the astonishing level of differentiation within our bodies.

Kenneth Wesson works as a keynote speaker and educational consultant for pre-school through university-level institutions and organizations. He speaks throughout the world on the neuroscience of learning and methods for creating classrooms and learning environments that are "brain-considerate."