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Human-engineered microbes are workhorses of the pharmaceutical and chemical industries, churning out biofuels, drugs, and many other products. But they can cause big problems if they become contaminated by other microbes or viruses or escape into the environment. Now, a new type of microbe that can survive only on artificial nutrients promises better security against such mishaps. The strategy, described in two papers in this week's issue of Nature, might ultimately be used to control genetically engineered plants or other organisms released into the wild to create products or clean up pollution.

In Milan, two German Shepherds trained for this particular task have certainly proven themselves accurate. The dogs were trained to detect specific chemicals in urine samples. One dog successfully identified prostate cancer in 98.7% of samples, and the other dog successfully identified prostate cancer in 97.6% of samples.

Many factors are known to be important in disease causation and these can include an individual's age, gender, genetic make-up and environmental factors that they have been exposed to, such as infectious agents or chemicals.

In biology classes, students are typically taught that spontaneous generation does not take place. And yet, at the origin of life, life had to arise without parents from abiotic processes. What were those processes that gave rise to the first life?  This case study uses an interrupted format to guide students through the Miller-Urey experiment of 1953, which showed that organic molecules could be produced from abiotic precursors and conditions thought to be prevalent on the early Earth. The case also addresses the more speculative implications about where these reactions may have taken place to create the organic building blocks of life on this planet. The first three parts of the case, which explore the Miller-Urey experiment, are ideal for introductory biology courses and take about 45-50 minutes to complete. The remaining sections, which explore whether such chemical reactions took place in outer space, were used in a non-major astrobiology course and require a further hour to complete.

This game reviews introductory chemistry, including organic compounds and chemical reactions. After you open the game in the PowerPoint attachment, click on slideshow and then view show to operate in full screen mode.  Clicking on a number in the gameboard brings you to a question. When that question has been answered click on the yellow box in the lower right corner and you'll be brought back to the gameboard screen.  Spaces for questions that have already been answered will now appear blank, just like on the TV show.  One way to organize this game is to divide your class into groups of 3-4 students, with a spokesperson for each group and a system for rotating among the groups.  Each group in turn can choose a category and point value, and you will show the question.  The group has a set time to decide on their answer.  If their answer is correct, they earn the points.  If their answer is not correct, the first spokesperson for another group to raise their hand can answer the question to earn the points (with the obvious exception of the true/false items).

In this video Paul Andersen explains how chemicals can cause both chronic and acute diseases. A discussion of the five main types of toxins; neurotoxins, carcinogens, teratogens, endocrine disruptors, and allergens is including. The LD50 method of determining toxicity as well as a discussion of bioaccumulation and biomagnification is is included.

"Now we have evidence that urinary odor signatures can be altered by changes in the brain characteristic of Alzheimer's disease," said Dr. Bruce Kimball, a chemical ecologist at the USDA National Wildlife Research Center, in a news release. "This finding may also have implications for other neurologic diseases."

The team, led by senior authors Qi Zhou and Xiao-Yang Zhao, both from the Institute of Zoology at the Chinese Academy of Sciences, took embryonic stem cells from mice and treated them to a series of carefully worked out steps that included first exposing the stem cells to testicular cells in newly born male mice. The scientists then recreated the chemical environment that sperm cells need to grow, including early development factors and sex hormones including testosterone, follicle stimulating hormone and a growth factor from the pituitary gland.

"A lot of people are still suspicious of genetically engineered foods," Profita said. "But they're also concerned about the environmental impacts of making them. A lot of the time, genetically engineered plants are engineered so that you can put more chemicals on the plants. And a lot of people don't want to be engaged in eating those types of foods." Environmentalists have worried about putting genetically modified fish in facilities near rivers, fearing the fish could escape into the wild. The company takes pains to say that these salmon are meant to be raised in tanks on land - not in netted pens in open waters. Otherwise, the operations are similar, Profita said.

Men, your sperm know how heavy you are. A new study reveals that sperm carry different chemical tags on their DNA depending on whether their owner is lean or obese. The findings suggest that men may be able to pass information about the availability of food in their environment down to their offspring, which could influence their child's odds of being overweight.

This animation was sponsored by the Center for Chemical Evolution, NSF, and NASA: http://centerforchemicalevolution.com/

3:35 video Enzymes are the critical ingredient in every organism that make life possible. They are catalysts and drive every chemical reaction that takes place in the human body, enabling our bodies to be built from proteins, carbohydrates, and fats. In this program from VEA we investigate the role of enzymes in detail, offering both theoretical and practical examples.

"After the Rainbow" is a video safety message focusing on preventing accidents in high school chemistry laboratories

On July 26, 1943, Los Angeles was blanketed by a thick gas that stung people's eyes and blocked out the Sun. Panicked residents believed their city had been attacked using chemical warfare. But the cloud wasn't an act of war. It was smog. So what is this thick gray haze actually made of? And why does it affect some cities and not others? Kim Preshoff details the science behind smog.

Their nervous systems have changed over time to fight off the powerful chemicals-an extraordinary example of evolution in action, according to a new study. "I've been wanting to understand how organisms could acquire neurotoxins, [which] requires an animal to reorganize their nervous system," says study coauthor Rebecca Tarvin, a biologist at the University of Texas at Austin and National Geographic Society grantee.

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.

This case study was written for an introductory course for biology majors who are first learning about embryonic development. The case is composed of several parts and involves a storyline about a team of researchers who find frogs and eggs in bamboo plants during a field study. Students consider what these observations mean, learn basics about the stages of animal embryonic development, and make connections to phylogeny and natural selection. Students then apply their understanding of animal embryonic stage development to the chemical atrazine in the environment by examining data from several experiments. As a concluding activity students write a letter to an agency or newspaper of their choosing stating their opinion surrounding the use of atrazine in the environment. The case proceeds in a progressive disclosure format and involves a combination of class discussion, small group work, and homework. Because the case focuses on very basic animal embryonic development, it would also be a great start to a developmental biology course or an embryology course.

This animation shows how glycolysis converts glucose into pyruvate through a series of enzyme reactions. It is the first of six animations about cellular respiration. These animations bring to life the molecular engines inside mitochondria that generate ATP, the main source of chemically stored energy used throughout the body.

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