.... and the chromosomes - DNA molecules are being copied exactly. The two identical copies of DNA are called a "pair of chromatids" and they are linked together by an item called a "chromomere". During this stage a store of ATP is also built up. [Best put a labelled diagram of a cell during Interphase here.] Prophase --------------------------------------- In this second stage changes to the cell become visible. The chromosomes condense, coiling up to about 5% of their original length, now clearly visible when a stain is added. The centrioles move to the opposite poles of the cell and small microtubules around the centrioles become visible (called "Asters"). The nuclear ....

.... of doubt. When metal is burned, its ash has a greater mass than the original substance. Stahl tried to cover himself by saying that phlogiston will take away from a substance's mass or that it had a negative mass, which weren't relevant to his original theories. In the Eighteenth Century Antoine-Laurent Lavoisier, in France, discovered an important detail in the understanding of the chemical reaction combustion of oxygen. He said that combustion was a chemical reaction involving oxygen and another combustible substance, such as wood. John Dalton, in the early Nineteenth Century, discovered the atom. It gave way to the idea that a chemical reaction was actually t ....

.... the only true form of light they had other than the moon. Fire had many disadvantages, one was that fire depended on fuel and needed proper conditions to operate (no rain, minimal wind). Another disadvantage is that fire, if not handled properly, could result in a brush fire or even burn down their shelter. An advantage was it was efficient when conditions were correct. It provided an inexpensive form of lighting, and could be used for cooking and heating. Due to the persistent problem of limited fuel, inhabitants looked for a way to prolong the fuel. (Thwig 29-34) The next step in lighting that followed was a candle. Candles offered one main advantage over the fire by itse ....

.... The way Giraffes give birth is standing up, they can even do it while sleeping. New born calves, which are baby giraffes, begin their lives by falling 6 feet to the ground. Usually a calve stands 6 feet tall and is able to stand after birth. They are highly attuned to danger thanks to their height and good sense of smell and eyesight. They can be fast and can reach speeds of up to 35 mph. Females spend over 12 hours a day looking, while males are less. Night mostly spent lying down ruminating, especially hours after dark and before dawn. A Giraffe has 2 ways of getting around which is walking and galloping. The long legs and short trunk decree an a ....

.... are results of volcanic activity. You see, even though neither plate is actually being subducted on two of the convergent plate boundaries, one plate is pushed a bit under the other normally. At the sea floor to continent boundary, the sea floor is subducted. As the plates move together, molten material from the mantle seeps up between the converging plates. The gap is closed as the plates move more into each other, locking the molten material in. This, by the way, happens at all of the convergent boundaries. After much time, pressure builds up as the molten material churns in its chamber. It gets hotter, and as we know from the laws of physics, heat rises due to its kineti ....

.... landscape. Sudden changes will look and feel forced. Simple shape pond shapes are best. Sharp curved edges or too many curves look artificial. Choose plants for the pond and its surroundings that make the pond look genuine. Plants at the water's edge are usually different from those found on the surroundings higher ground. Especially reminiscent of natural ponds are large plant's that leaves overhanging the water's edge, and plants with long thin, grassy foliage that grows in the shallows. These will all help to cover the water edge, which is almost never seen in a natural pond. Most nurseries sell aquatic plants. A pond that is meant to look natural requires much les ....

.... simply because it is too small. Only a very large star has the potential to become a black hole. The definitions of black boles are somewhat sceptical. Generally, a black hole is an area of super-concentrated mass. So concentrated, that no object can escape its gravitational pull. In other words, once you get caught by it’s graviational pull, you aren’t getting out again. The velocity you need to break away from a graviational pull is called the "escape velocity". Roughly, earth’s escape velocity is about 25,000 M.P.H. (11.2 kilometers/second). Earth’s mass is nothing compared to the mass of a star that has the potential to become a black hole. A black hole has so ....

.... continues to increase the way it is currently. In third world countries their food supplies are becoming increasingly scarce because of their increasing populations. In these third world countries the rich-poor gap is increasing creating the potential for large parts of the population to starve. Paraphrasing Ehrlich's ideas in chapter can be explained as; there is only so many resources and as population increases those resources will soon be depleted. Ehrlich uses historical population research to lead to the conclusion that in 90 years the population could be well over the earths carrying capacity. In third world countries where population control is rarely used po ....