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The complex systems of high school dating and chemical reactions may have more in common than you think. Explore five rules for speeding up chemical reactions in the lab that might just land you a date to a dance!

You will learn about "Dalton's Atomic Theory" in this video. John Dalton was an English chemist who is very well known today for his work in the development of atomic theory. Let us learn the postulates of Dalton's atomic theory. All matter, whether an element, a compound or a mixture are made up of very tiny particles called atoms. All atoms of a given element are identical in size, mass and chemical properties. Atoms of different elements differ in size, mass and chemical properties. Atoms are indivisible particles which can neither be created nor destroyed in a chemical reaction. Atoms combine together in fixed whole number ratios to form compounds. In a chemical reaction, atoms only get rearranged. An atom of an element does not change into the atom of another element.

The Miller-Urey experiment was the first attempt to scientifically explore ideas about the origin of life. Stanley Miller simulated conditions thought be common on the ancient Earth. The purpose was to test the idea that the complex molecules of life (in this case, amino acids) could have arisen on our young planet through simple, natural chemical reactions. The experiment was a success in that amino acids, the building blocks of life, were produced during the simulation. The finding was so significant that it kick started an entirely new field of study: Prebiotic Chemistry. Scientists now have reason to believe that the gases used in the Miller-Urey simulation were not actually the same as those of the ancient atmosphere. Because of this, many experiments have since been done, testing a wide variety of atmospheres and different environmental conditions. The results are overwhelming: the molecules of life can form under a wide variety of ancient Earth-like conditions. Many questions about the origin of life remain to be answered but these findings give strong support to the idea that the first living cells on Earth may have emerged from natural chemical reactions.

2 min -intro overview Chemical reactions need a catalyst to provide a site for the reaction and control the energy flow. Catalysts are made up of enzymes.

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 interrupted case study examines basic concepts of chemical bonding by telling the story of "Madison," a young girl eager to learn how her hair can transition from natural curls to straight, smooth tresses. The case can be used to teach or review the major categories of bonds (ionic, covalent and hydrogen), major macromolecules of life, and hydrolytic and dehydration reactions. It also explores how chemical relaxers and heat through blow drying and flat-ironing can change the nature of straight, wavy and curly hair through the disruption of protein shape. Students will thus learn what it means when a protein has become denatured and how various variables such as pH, heat and salts can lead to the unraveling of the three-dimensional shape of proteins. This case is suitable for an AP high school course, or for an introductory biology or chemistry course for majors or non-majors. This activity can also be used as a review of basic biology and chemistry for students in an upper-level biochemistry course.

Common in cuisine all around the globe, onions are renowned for their ability to make us all look like cry babies. In Reactions' latest video, we get to the bottom of this teary phenomenon and reveal exactly what chemical mechanisms trigger it. The video also features a few chemistry-backed tips you can try at home to stop the tears before they start.

The Hawaiian Bobtail squid has a remarkable symbiotic relationship with a species of marine bacteria that can produce light by a controlled chemical reaction. Also featured on the HHMI DVD, Exploring Biodiversity: The Search for New Medicines, available free from HHMI.

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).

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.

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.

It's peak cold and flu season, and mucus is making many of our lives miserable. But despite being a little icky, phlegm gets a bad rap. This germ-fighting goo contains cells and chemical compounds that help us power through a cold. You can also think of mucus as a traffic light for your health - what turns up in our used tissues can be a useful clue about the inner workings of our immune systems.

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