.... episode on the other hand is almost opposite of a manic one. During a depressive episode, the person is sad, irritable, has low self-esteem, negative thoughts, and loss of interest in usual activities. They feel like they’re worthless and hopeless. They also have negative thoughts towards the past and future. Many people go through guilt, crying, or having suicidal thoughts. Unlike a manic episode, the person has lack of energy, and either an appetite loss or gain. Manic depression is a recurrent illness, so a person usually has more than one episode. These episodes can last from weeks to months. They occur whenever and have no certain pattern. Someti .....

.... severely polluted areas, rain can be as acidic as the acids lemon juice and vinegar. Rain which is very acidic can cause damage to trees, lakes, wildlife, buildings, and human health. Some air pollution comes from natural sources, but most is human made. The burning of coal and oil (fossil fuels) by factories, homes, and cars is the main source of chemicals that cause . Power stations emit large amounts of sulfur dioxide and also nitrogen oxides, while car exhaust contains large amounts of nitrogen oxides. Once is formed, it can stay up in the clouds for a long time. These clouds can be carried off by the wind to other areas, sometimes hundreds of mi .....

.... Plant Cell for only a couple of reasons. One is how the Plant Cell has a cell wall and the Animal Cell doesn’t. The cell wall protects and gives structure to the cell. Then there is the Nucleus, which serves as a control center for the cell. Inside the Nucleus there are one or more Nucleoli. They are dense, granular bodies that disappear at the beginning of cell division and reappear at the end. Then you have the Cytoplasm. This is the watery material lying within the cell between the cell membrane and the nucleus. The Cytoplasm also contains organelles, which have specific functions in the cell metabolism. Then there are the Golgi Bodies, which serve as .....

.... . . . . 22 Introduction "Our understanding of the way the natural world works - and how our actions affect it - is often incomplete. This means that we [must] exercise caution, and special concern for natural values in the face of such uncertainty and respect the 'precautionary principal'." - Ontario Minister of Natural Resources, 1991 The History of the Forest Forests have long been recognized as having vast power, both through their potential and how it has been viewed by humans, as well as through their effect on humans in sometimes subtle ways. The inherent properties of wood have always made it attractive as a versatile resource but there are .....

.... ................ 29 MECHANISMS FOR GENETIC VARIATION .......................... 31 GENETIC VARIATION AND SPECIATION .......................... 35 DARWIN'S FINCHES .......................................... 37 SPECIATION vs. CONVERGENT EVOLUTION ....................... 39 CONCEPT OF ADAPTATION ..................................... 41 PUNCTUATED EQUILIBRIUM ....................................43 VALUE/LIMITATIONS: THE THEORY OF BIOLOGICAL EVOLUTION .... 45 ALTERNATE EXPLANATIONS OF BEING ........................... 47 CONCLUSIONS ............................................... 48 INTRODUCTION Theories explaining biological evolution have been bandied about si .....

.... all kinds of things. All DNA molecules consist of a linked series of unites called nucleotides. Each DNA nucleotide is composed of 3 subunits: a 5 carbon sugar called deoxyribose, a phosphate group that is joined to one end of the sugar molecule, and one of several different nitrogenous bases linked to the opposite end of the deoxyribose. There are 4 nitrogen bases called adenine, guanine, thymine, and cytosine. In DNA adenine pairs with thymine and guanine with cytosine. Medicine's ability to diagnose continues to exceed its ability to treat or cure. For example, Huntington's Chorea is an inherited disease that develops between the ages of 30 and 45 .....

.... the first step in the birth of a hurricane. With the lid off, the warm, moist air rises higher and higher. Heat energy, released as the water vapor in the air condenses. As it condenses it drives the upper drafts to heights of 50,000 to 60,000 feet. The cumuli become towering thunderheads. From outside the storm area, air moves in over the sea surface to replace the air soaring upwards in the thunderheads. The air begins swirling around the storm center, for the same reason that the air swirls around a tornado center. As this air swirls in over the sea surface, it soaks up more and more water vapour. At the storm center, this new supply of wa .....

.... and movement (E.B. 1999) but we can not confuse the Aedes aegypti with any other mosquito for it has a very distinct look to it as well as a specific habitat. It has many related species and it’s geographic distribution is extremely wide and varied. The Aedes aegypti, with regard to both sexes, are generally similar in coloration (Womack 1993). The female adult is noticed by it’s small dark figure that is colored by white markings and banded legs. Its proboscis or snout is mostly black with regard to the white palp tips (Russel 1996). The dorsal pattern of white scales on the scutum is in the shape of a ‘lyre’ with two central based stripes .....