.... been left to burn uncontrolled for weeks. Fires were caused by different sources such as lightning or human hunters who wanted to chase animals out of the woods. As prolonged as these fires were, they had limited catastrophic effects on the nomadic humans. This is due to the low population density and the fact that the fires were not very intense. As people began to change from a hunting-gathering society to agriculturists, they settled in communities. Homes built among the wild brush were perfect prey to wildfires. Initially, wildfires were put out immediately and people were barred from setting fires in open spaces. Due to the policy of fire suppression, only one pe ....

.... theories which are used to explain the creation of the universe. The first theory is the infamous Big Bang Theory, which will be detailed later. The second is the Steady State Theory. (Weinberg, 1977) The later hypothesis was created to replace the common belief that the universe was completely static. The expansion of the universe was discovered in 1929 when Edwin Hubble discovered that every galaxy in the universe was moving away from each other, this meant that the universe was expanding. Hubble found the movement of the galaxies by using a phenomenon known as the Doppler effect. This effect caused bodies moving away from an observer to have a "red-shifted" spectrum (t ....

.... phase. In this phase, the centrioles begin to replicate, the DNA replicates, and all of the preparations are made to be ready for to take place. The chromatis is coiled up and consists of loose threads. In prophase, the next longest stage, the chromatin becomes chromatids which later form chromosomes. They are attached to the centrioles by spindle fibers. The chromosomes are lined up in the center of the celll. The nucleolus and nuclear membrane disappear. In the next phase, metaphase, the chromosomes line up along the metaphase plate. The plate is the midpoint of the cell between the two centrioles which are located at opposite poles. During anaphase, the centrioles start ....

.... is found mostly in stars, where it goes through nuclear fusion with hydrogen. Most Helium comes from natural gas taps in North America. It is used in balloons and divers use it with oxygen to breath easier and to not get sick or dizzy. Neon is an element that is lighter than air. The element is found most common in the atmosphere of the earth. It is also found in the earth’s crust. Sir Walter Ramsey and Morris W. Travers discovered it in 1898. Its uses include electric signs, lamps, and lasers. Argon is the most abundant and most used noble on earth. Sir Walter Ramsey discovered it by Lord Rayleigh and in 1894. Argon makes up about 1.2 % of the earths atmospher ....

.... itself further away from it's source causing more than local problems. Sulfur Dioxide (SO2) is released by fossil fuels when they undergo combustion. Power plants and other fossil fuel burning industrial areas release various forms of nitrous oxides (Nox). These two chemical compounds combine with the water in the atmosphere to form what is known as acid rain. The main reason that has prompted legislation of industrial emissions from governments is because of the negative effects they can have on the environment. Acid rain is harmful to the environment because of it's low pH. It can harm the biotic components of earth, and also the abiotic components. It's h ....

.... germinating. We quickly noticed something that appeared like an air bubble squirting out something green. This was our fern spore which was germinating. Next, we removed a few of the germinating spores from the petri dish and put them under a compound microscope scope. We found the spore wall and observed how the developing gametophyte had broken through the wall, as instructed by our lab manuals. One could also identify the chloroplasts with in the cell. We then put up our dishes for another week. The third week of our fern lab we identified the difference between male and female gametophytes. We did this by taking a culture from our petri dish and placing it under a dis ....

.... the ball will reach the fence. Trajectory is also seen in basketball, where players must shoot the ball with enough arch to get over the front of the rim, and go through the hoop. The energy required to do this comes from not only the arms, but the legs as well. The medical field has seen enormous breakthroughs because of principles of physics. Doctors are now able to use lasers for surgery. Lasers are based on the physical principle of light, and are devices for the creation and amplification of a narrow, intense beam of coherent light. New laser microsurgery can actually alter the shape of the cornea in the eye so the patient's eyesight can return to normal, and he/s ....

.... mania. People with seasonal affective disorder typically suffer from depression only during autumn and winter, when there are fewer hours of daylight. In dysthymia (pronounced dis-THI-mee-uh), people feel depressed, have low self-esteem, and concentrate poorly most of the time—often for a period of years—but their symptoms are milder than in major depression. Some people with dysthymia experience occasional episodes of major depression. Mental health professionals use the term clinical depression to refer to any of the above forms of depression. Surveys indicate that people commonly view depression as a sign of personal weakness, but psychiatrists and psychologists view ....