... ways to tamper with or harm a river, a large dam usually has the most immediate and far-reaching effects because of the huge changes it causes to river circulation system. Some 40,000 large dams, most of which were built in the past 50 years, now obstruct the world's rivers. More than 400,000 square kilometers--an area larger than Zimbabwe, and 13 times the size of Lesotho. Volta Reservoir behind Ghana's Akasombo Dam, flooded 4% of that nation's land area. In the United States, whose 5,500 large dams make it the second most dammed country in the world, we have stopped building large dams, and are now spen ...

... are colorless and transparent, when combined with other elements its color can range from pastels to black. Diamond is a poor conductor of heat and electricity. Until 1955 the only sources of diamond were found in deposits of volcanic origin. Since then scientists have found ways to make diamond from graphite and other synthetic materials. Diamonds of true gem quality are not made in this way (Beggott 3-4). Graphite is another form of carbon. It occurs as a mineral in nature, but it can be made artificially from amorphous carbon. One of the main uses for graphite is for its lubricating qualities. Another is ...

... are parthenogenic and for most of the year populations consist entirely of females which reproduce asexually. As winter (or sometimes spring) approaches males appear and sexual reproduction occurs typically involving the production of resistant, over-wintering eggs. Such eggs are usually enclosed in a purselike ephippium that rests in the sediment at the bottom of the lake or pond until spring at which time the eggs hatch. 1. Daphnia magna. Take a small culture dish to the instructor to receive a few living D. magna. This is a very large species, as go, and one that is easily cultured in the laboratory. Retur ...

... solution. The best results came from galactose, which produced .170 ml/minute of carbon dioxide. Followed by glucose, this produced .014 ml/minute; finally, sucrose which produced .012ml/minute of Carbon Dioxide. The test solutions water and glycine did not release Carbon Dioxide because they were not a food source for yeast. The results suggest that sugars are very good energy sources for a cell where amino acid, Glycine, is not. INTRODUCTION Fermentation is an anaerobic process in which fuel molecules are broken down to create pyruvate and ATP molecules (Alberts, 1998). Both pyruvate an ...

... 2000 U.S. soldiers were affected with this unknown virus that was quickly found to be carried through field mice. The natural territory of this virus included parts of Japan, Korea, northeastern China, and southeastern and central Russia. Between 1955 and 1977, this virus caused many more infections along with fatalities. Throughout the 1970s, eleven other strains of es were found in Korea and Eurasia. In 1976, Hantaan virus was isolated from the Apodemus agreavius coreae mouse. Using the microscope, one could see the round microbes that were stacked in rows along the epithelial lining of the lungs (CDC websit ...

... tiny bubbles of air in the ice core at different levels below the present ice surface. The deeper layers in the ice core correspond to times in the more distant past. The air bubbles can be analysed for the relative abundance of carbon dioxide to estimate atmospheric carbon dioxide levels at times extending back 160 000 years. Through the ice sheet, we know that 160 000 years ago, carbon dioxide concentrations were about 180 ppm and have presently exceeded 350 ppm. 5) There are mainly 3 major sources of carbon dioxide presently and historically. They are industrial activity, land use change and cement plant ...

... making up different gases must be different. Dalton's exceptional gift for recognizing and interpreting patterns in experimental data lead him from a problem in meteorology to the idea of atoms as fundamental constituents of matter. He realized the vital theoretical connection between atomic weights and weight relations in chemical reactions. He was the first to associate the ancient idea of atoms with stoichiometry. The existence of atoms was first suggested more that 2000 years before Dalton's birth. (Newton's speculations about atoms in the Principia were carefully copied by hand into Dalton's notebooks.) Ato ...

... the orbits of the planets around the Sun were calculated. In the 17th century, astronomers pointed a new device called the telescope at the heavens and made startling discoveries. But the years since 1959 have amounted to a golden age of solar system exploration. Advancements in rocketry after World War II enabled our machines to break the grip of Earth's gravity and travel to the Moon and to other planets. The United States has sent automated spacecraft, then human-crewed expeditions, to explore the Moon. Our automated machines have orbited and landed on Venus and Mars; explored the Sun's environment; ob ...

... half of what an average hard drive holds up to today. A hard drive is what all the information you install in to your computer goes. Inside a hard drive it looks like large CD:ROM , but this one is magnetic. If you open one up it will look like egular record player. The needle is what writes the information onto the hard drive. The needle writes by the magnetic force that pushes it down on to the disk. Once it is on the hard drive , whenever you turn on your computer the information is always there for you when you need it. A CD:ROM looks like a music compact disk , but they are not that much alike. First a C ...

... without any original grounds for belief. Over time more and more people looked into and they developed possibilities of how it occurred. Many theories were developed, but someone always disproved them. Recently with the discovery of genetic mutation and a new understanding of genes and DNA, the evidence supporting evolution has greatly increased. Charles Darwin was one scientist who helped to increase the evidence supporting evolution. Darwin developed the idea of “natural selection� where living things that reproduced in large numbers and survived became dominant and other living things ad ...