... into space through the earth's atmosphere. But, because of increased carbon dioxide and methane in the earth because of emissions from polluters such as factories and cars, excess energy is trapped in the earth's atmosphere and causes a warming of the earth called "Global Warming." Starting in the mid-1700s, human activities began to alter the composition of the atmosphere. Vast supplies of charcoal, and later coal and oil, fed the growing fires of the Industrial Revolution. The carbon stored in these fuels was released to the air as carbon dioxide - a gas that traps heat in the atmosphere. Today, for every one ...

... simplicity this essay will concern itself with only the brain of a rat. This essay will thus discuss the evolution of relevant behaviourist and neurophysiological theories, the most important being O'Keefe (1991); Muller, Kubie, Bostock, Taube and Quirk (1991); and Rolls (1991). The behaviourist theories proposed that a reward or aversive object/event will motivate a rat to move towards or away from the location along a reward gradient, and this has been shown to be the case with rats in a maze situation (O'Keefe, 1983). Indeed, this situation does not require the rat to have a concept of absolute space; it may dep ...

... joined together basically the same way, and that the smallest part of a chemical compound was a molecule. He said that "All atoms of an element have the same chemical behavior, but different elements have atoms with different chemical properties." Scientists weigh gases by holding the same amount of a gas in a container and then wighing it. In the 20th century, most scientists used oxygen as the standard gas to compare other gases' weights. It is relativly easy to measure the weights of liquids and sloids, the same procedure for gas is followed, more or less. In the early 1960s, though, the international union ...

... fever disease. The Ebola Zaire in Kikwit spread quickly, but investigation and control of the outbreak come from a combined effort of medical teams from the U.S. Center for disease Control and Prevention (CDC), the World Health Organization, and from other health organizations in Belgium, France, and South Africa. Since July 1, 1995, 233 deaths have been reported among the 293 cases, in Africa (Garrett 195). Since 1976, researchers have searched for an origin and cure of the virus. Scientist have carried out numerous studies and investigations. Therefore, we now know what the virus is capable of doing, how ...

... in order to spring the trap. The trap will close in less than a second, in ideal conditions, and if an insect is caught, the trap will seal shut and start secreting digestive juices. If the trap closes empty, it will slowly open in about a day. It may take a week to digest a housefly, and when the trap reopens, the shriveled shell of the insect is left behind. A trap may catch and digest up to three insects, after which the leaf turns black. Older leaves blacken and die regardless of how many insects are caught and the plant continually sends out new leaves during the growing season. Venus flytraps usually grow alo ...

... probable by the scientific community is that the hole was created by man made substances. These substances are chlorofluorocarbons (CFC's). CFC's are found to be emitted into the atmosphere by solvents, refrigerators, and spray can propellants mainly in the Northern Hemisphere. CFC's disperse throughout the stratosphere and breakdown to release chlorine. Chlorine by itself is a very stable compound, but when in the stratosphere it binds to and destroys ozone. This is a cyclic process and therefor means that one chlorine can destroy many ozone molecules (Figure 1.2) During the winter in the Antarctic the circump ...

... carbon monoxide to enter the atmosphere are the exhausts of cars, the burning of fossil fuels, and the oxidation of natural methane. Carbon dioxide is caused by the consumption of fossil fuels only and it causes the possible greenhouse effect which has global warming as an outcome. Hydrocarbons are caused by the combustion of oil and petrol and it effects the environment with carcinogen. Carcinogen is a chemical agent that causes cancer. Sulphur dioxide is certainly one of the major atmospheric pollutants considered that it causes stinging eyes, lung damage, asthma, and acid rain. It is the result of coal-fired ...

... 43ml of water, put the pondweed in it and place it in the clamp. I would place the ring binder around the clamp stand surrounding the water base. Finally, I would plug in the lamp and place it 10cm away from the pondweed. I done a preliminary experiment to get an idea how to do the main and proper experiment and what would happen in the experiment. In the preliminary experiment we didn’t use the safeguards so it wasn’t fair experiment. We did this because it gave us the idea what problems we might face when we did the main experiment and gave us the idea how to do it. The pondweed should create ...

... can get extinct any time, if it is endangered today it might be extinct tomorrow or extinct in the future. Or it might not happen like that. If you leave it alone and do not harm it, it might have baby’s and have more of its kind. A species is named endangered when of its kind occurs in a low number. About 1000 species in the world are named endangered, or are in threat to be extinct. I never knew that some kinds of birds were in danger. We can help these animals and plants by making laws that you are not allowed to hunt or kill any animal that is in danger of extinction. Government Involvement Only since ...

... by a healthy immune system. Almost anyone at any age can get mononucleosis. Seventy to 80 percent of all documented cases, however, involve persons between the ages of 15 and 30. Both men and women are affected, but studies suggest that the disease occurs slightly more often in men than in women. Doctors estimate that each year 50 out of every 100,000 Americans have mononucleosis symptoms. Among college students, the rate is several times higher. Mononucleosis does not occur in any particular "season," although authorities in colleges and schools, where the disease has been well studied, report that they see most ...