... sometime after lobe-finned fish, and before the first fully terrestrial vertebrates. The earliest tetrapod known is Acanthostega. It is also considered the most primitive tetrapod. It is very close to its fish ancestry, but still anatomically far from its terrestrial relatives. These creatures still lived in water, but they had a lot of the terrestrial tetrapod anatomical characteristics. Introduction: Before tetrapods existed, all vertebrates were confined to living in aquatic habitats. The only animals that lived on land were arthropods. Through natural adaptations, the fish developed into amphibians. This colossal stage of change made necessary the evolutio ...
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... age of Mars has been reported to be between 3.6 billion and 1.3 billion years old, "depending on who you ask" (Erjavec, 1). These ages come from the estimated ages of meteorites found on Earth that are believed to have originated on Mars (Meteorites from Mars, 1). The meteorites were dated using radiometric dating methods (Erjavec, 1). The most widely accepted theory of life on Mars is that of the recently conceived primitive, or microscopic, life may have existed on early Mars. "A NASA research team at the Johnson Space Center and at Stanford University has found evidence that strongly suggests primitive life may have existed on Mars more than 3.6 billi ...
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... entomologist C.V. Riley was quoted in an article written by Sean Adams for Agricultural Research. Adams uses Riley’s quote from 1882 saying that the evidence for the use of natural enemies and parasites to control pests is sufficient to support their use. (16). Even so, pesticides have been used for centuries. In James Whorton’s book, Before Silent Spring, he describes agriculture before the Industrial Revolution. He writes that farmers in the 1800's used arsenic and sulphur to stop insects and molds from harming their crops. Even then it was known that arsenic caused skin lesions, nausea, vomiting, diarrhea, and swollen, painful hands and feet. In England i ...
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... All engineering jobs are paying well, proving that highly skilled labor is what employers want! “There is clear evidence that the supply of workers in the [unskilled labor] categories already exceeds the demand for their services,” says L. Mishel, Research Director of Welfare Reform Network. In view of these facts, I wonder if these trends are good or bad for society. “The danger of the information age is that while in the short run it may be cheaper to replace workers with technology, in the long run it is potentially self-destructive because there will not be enough purchasing power to grow the economy,” M. B. Zuckerman. My feeling is that the trend from uns ...
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... alternating episodes of serious mania and depression. An affected person’s mood can swing from excessive highs (mania) to deep hopelessness (depression), usually with periods of normal mood in between. Some individuals may display mixed symptoms of both mania and depression at the same time, while others may have fewer symptoms of mania (also referred to as hypomania). The type severity, and duration of mood episodes may vary. Some individuals may experience excessive mania, or excessive depression, and some may experience an equal amount of both. The mood episodes can last for a few days to as long as several months, especially when left untreated or n ...
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... would also be true. A laser is useful because it produces light that is not only of essentially a single frequency but also coherent, with the light waves all moving along in unison. Lasers consist of several components. A few of the many things that the so-called active medium might consist of are, atoms of a gas, molecules in a liquid, and ions in a crystal. Another component consists of some method of introducing energy into the active medium, such as a flash lamp for example. Another component is the pair of mirrors on either side of the active medium which consists of one that transmits some of the radiation that hits it. If the active component in the laser ...
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... this matter. Evolutionists feel strongly about their stance on the issue of presenting creationism to America's classroom. They feel that by bringing this medium into schools, the Christians will be able to "further advance their various agendas" (Flank) by forcing their religious beliefs on students who do not believe in God, or in the same god. This is where the separation of Church and State comes into play. Evolutionists are adamant about keeping religion out of school, according to the guidelines of the Constitution. The Supreme Court ruling that stated that creation science is religious in nature and cannot be legislated in the classroom (Flank) i ...
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... solids, and gas. All matter is made up of tiny particles called atoms. An atom is the smallest unit of matter that can exist and still be recognized. You and all the things around you are made of matter. Since we all live at the surface of the earth where the acceleration of gravity is relatively constant, it has been natural for us to confuse the concepts of mass and weight. To study the difference, we need to separate these two "parameters." We could either leave the earth's gravitational field so that we would have no weight, or create an experimental situation where weight is not a factor. An easy way to do this is to use floating objects. Floating object ...
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... have improved, they often stop taking the drug. Just because the symptoms have disappeared it does not mean the disease has gone away. Prescribed drugs should be taken until all the medicine is gone so the disease is completely finished. If it is not, then this will just give the bacteria some time to find a way to avoid the effects of the drug. One antibiotic that will always have a long lasting effect in history is penicillin. This was the first antibiotic ever to be discovered. Alexander Fleming was the person responsible for the discovery in 1928. In his laboratory, he noticed that in some of his bacteria colonies, that he was growing, were some clear spo ...
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... Indicator was substance that had distinctly different colors in acidic and basic media. Phenolphthalein was a common indicator which was colorless in acidic and neutral solutions, but reddish pink was result in basic solutions. Strong acid (contained H+ ion) and strong base ( contained OH ) were 100% ionized in water and they were all strong electrolytes. Procedure: Part A. Investigating solid NaOH for use as a possible primary standard First of all, The weight of a weighting paper was measured in analytical balance, then added two pellets of NaOH and reweighed the total amount of those. At the end of the lab, reweighed the combination and recorded all re ...
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