.... unprotected sex or share needles or syringes with. AIDS and HIV are two different viruses, but HIV well eventually turn into AIDS. About half the people with HIV develop AIDS within 10 years, but between infection with HIV, the onset for AIDS can vary greatly. The severity of the HIV related illness or illnesses will differ from person to person, according many factors but mostly to the overall health of the individual. The new advances in technology are helping postpone the advancement of the disease. Lets start at the beginning. First, lets learn what AIDS is. AIDS is an acquired defect in your immune system. The passing of any bodily fluids could technically be us ....

.... of marsh grasses or mudflats extend into calm waters that then follow the curve of an expansive barrier beach. Wherever there are estuaries, there is a unique beauty. As rivers meet the sea, both ocean and land contribute to an ecosystem of specialized plants and animals. At high tide, seawater changes estuaries, submerging the plants and flooding creeks, marshes, panes, mudflats or mangroves, until what once was land is now water. Throughout the tides, the days and the years, an estuary is cradled between outreaching headlands and is buttressed on its vulnerable seaward side by fingers of sand or mud. Estuaries transform with the tides, the incoming waters seemingly br ....

.... the age of 14 or 15, koalas reach their sexual maturity at the age of two. The female produces one baby every other year. The koala almost never produces twins. In the female's pouch, there are two nipples. The female koala gives birth after a 20-35 day gestation period. When the joey (baby koala) is born, it is no longer than 2 cm and weighs no more than a 1/2 gram. The joey stays in its mother's pouch for 5-7 months. The term "joey² is used when you are talking about a baby marsupial. The mother gives "pap² to the joey, a liquid from the caecum (which is similar to the human organ, appendix.) This is thought to give the joey the ability to eat only eucalyptus ....

.... Pathogens are disease causing bacteria, viruses, and protozoa. They usually come from human sewage. As pathogen numbers increase, so does the risk of human health. Biochemical Oxygen Demand: Organic wastes that decay in a body of water. decrease the amount of oxygen found in it. The living things in the lake need oxygen to survive. If the oxygen level is depressed to zero, all fish in the lake die. Any decomposition that does not contain oxygen starts to generate noxious gases such as Hydrogen Sulfide. Pulp and paper mills, and municipal sewage causes BOD. Nutrients: Nutrients, particularly nitrogen and phosphorus, enrich waters and accelerate the aging of lakes and s ....

.... called rods and cones do to their shape. The cones are responsible for converting the color. Each cone contains visual pigments that are sensitive to one of three wavelengths of light: red, green and blue. Normally, all colors of the spectrum are able to be matched by mixtures of only three color sensitivities. Therefore, the huge variety of colors we see are a response to different compositions of wavelengths of light. The rods are responsible for encoding white and black. results when one or more of the cone cells fail to function properly. One of the visual pigments may be functioning abnormally, or be absent altogether. There are several different types of , howev ....

.... Parkinson’s and Cystic Fibrosis. Pigs could be cloned to produce organs that would not be rejected by humans. Cloning could give couples who would like children, but could not have any, a chance to have them. This process would also let single women have a child without using in-vitro fertilisation or artificial insemination. Cloning could also make a copy of a deceased child for the parents. Also it would be a very useful tool for historians as people such as Hitler would be able to be recreated and studied to find out what their motivations were. Besides from all these good points cloning also has bad points. The biggest problem with cloning on a large scale is ....

.... of food in the Arctic, they must be able to travel a great distance at a good speed. Looking at a polar bear you will probably notice that it is bowlegged. This means that their huge paws point inward. Having their paws in this position helps them grip the slippery ice. Another specialized feature of its paws is that they have pads of dense fur on the bottoms. Polar bears are the only bears that have this feature. These pads help the bear retain heat and to grip the ice and provide better traction. Polar bears are fast movers. When on uneven ice the bear will “trot”, moving its legs on opposite sides in unison. It can trot at 12 to 18 miles per hour. When it is ....

.... whether to isolate probes for the other chromosomes, or whether we should utilize the eight we have," he says. Dr. Willard is currently negotiating with an American company to develop prenatal diagnostic tests, which, because the current tests are time consuming and technically difficult to do, are restricted to women over 35 and those who have a family history of chromosomal abnormalities. Prenatal tests using Willard's probes would be much simpler and faster to perform and could be available to all pregnant women who wish to take advantage of the technology. Current prenatal testing involves growing fetal cells in vitro and examining them, over one or two months, to ....