... like love, grief and even embarrassment to describe the behavior of these large, social birds. At the same time he did not forget that all romance - animal and human - is tied intimately to natural selection. Natural selection brought on the evolution of males and females during prehistoric epochs when environmental change was making life difficult for single-sex species such as bacteria and algae. Generally, these reproduced by splitting into identical copies of themselves. New generations were thus no better than old ones at surviving in an altered world. With the emergence of the sexes, however, youngsters acquired the qualities of two parents. This mea ...
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... a nuclear pore, DNA is too large a molecule to do this, to the cytoplasm. In the cytoplasm there are free transfer RNA [tRNA] molecules which hve three protruding bases these sets of three on the tRNA are called anti-codons. Each tRNA molecule attracts different amino acids, of which there are around twenty, and they "stick" to the tRNA and depending on which tRNA molecule it is it wil attract a diferent amino-acid.On the RNA every three bases are called codons these are complementary to the anti-codons of the tRNA. For instance a codon of - GAA - would pair with the anti-codon- CUU -. In this fashion weak hydrogen bonds form between the tRNA and RNA molecules. T ...
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... the “fight” or “flight” hormone. The actions of epinephrine and norepinephrine are generally similar, although they differ from each other in their effects. Norepinephrine constricts almost all blood vessels. Norepinephrine is formed by intravenous infusion to combat the fall in blood pressure associated with types of shock. Norepinephrine is formed in the body from the amino acid tyrosine, and epinephrine is formed from norepinephrine. Mineralocorticoids steroids control the overall body fluid. Mineralocorticoids are critical to regulate concentrations of minerals in extracellular fluids. The major target of aldosterone is the distal tubule of the kidneys. Th ...
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... can be caused by runoff, hurricane waves, tsunami (seismic sea waves), and hurricane rains. Coastal flooding can not only take part on oceans but it can also take part on lakes. Coastal flooding can be a great danger because coast lines are very densely populated areas. In the United States in the early 1990's 50% of the population was on a coastal county.1 Although they shrink before reaching shore, wind generated waves have been spotted to be as high as 30 m (100 ft) in the middle of the ocean.2 In 1970 a major storm in the Bay of Bengal produced heavy seas that flooded regions of East Pakistan, killing about 200,000 people.3 River flooding can happen ...
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... ships. The world fleet of commercial boats dump over 5,550,000 plastic, metal, and glass containers into the ocean in a single day.2 The most harmful of these is plastic. Sea mammals such as birds and dolphins often get tangled in the plastic six-pack rings, fishing lines, and net that humans discard into the ocean waters. Once entangled, they are unable to free themselves which can cause deep cuts, starvation, and drowning. Many ocean mammals have died as a result of ingesting these plastic items. In 1985, a sperm whale beached itself on a New Jersey shore; a mylar balloon was lodged in its stomach, and three feet of ribbon in its intestines. Most plastics take hu ...
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... explored it. The light is the result of a biochemical reaction in which the oxidation of a compound called "Luciferin" and the reaction was catalyzed by an enzyme called "Luciferase". The light generated by this biochemical reaction has been utilized by scientists as a bioindicator for Tuberculosis as well as heavy metals. On going research involving bioluminescence is currently underway in the areas of evolution, ecology, histology, physiology, biochemistry, and biomedical applications. History of Bioluminescent Fungi The light of luminous wood was first noted in the early writings of Aristotle which occurred in 382 B.C.(Johnson and Yata 1966 and Newton 195 ...
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... close to the sun, and has no substantial atmosphere, it has the greatest temperature range of any planet or natural satellite in our solar system. The surface temperature on the side of Mercury closest to the Sun reaches 427 degrees Celsius, a temperature hot enough to melt tin. On the side facing away from the Sun, or the night side, the temperature drops to -183 degrees Celsius. Scientists have detected a magnetic field surrounding Mercury, though it is not as strong as the field around the Earth. Scientists theorize that Mercury's field is due to an iron-bearing core or possibly to the solar winds. Mercury's atmosphere is very thin and is composed of helium ...
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... You would think of this as the end, but only an explosion is needed to wake up and give life to a new universe. Therefore, trapped forever in the cycle of rebirth. As humans we also travel through a cycle of rebirth according to the Hindu religion. We are all trapped on the Wheel of Samsara trying to break free. It is only possible to escape through the laws of Karma. Karma is simply how you act in this life determines what you are after your rebirth. For example, if you live each life being the best Hindu you possible can eventually your soul or Atman will be released and reach liberation. If you decide to go to the other extreme your Atman will co ...
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... Having their paws in this position helps them grip the slippery ice. Another specialized feature of its paws is that they have pads of dense fur on the bottoms. Polar bears are the only bears that have this feature. These pads help the bear retain heat and to grip the ice and provide better traction. Polar bears are fast movers. When on uneven ice the bear will “trot”, moving its legs on opposite sides in unison. It can trot at 12 to 18 miles per hour. When it is running, it can reach speeds of up to 35 miles per hour. The bear can travel around 50 miles on an average day. The polar bear is also an expert swimmer. The bear has a long neck with a smal ...
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... which are said to be a water pollutant. Most laundry detergents contain approximately 35% to 75% sodium triphosphate (Na5P3O10), which serves two purposes. Providing an alkaline solution (pH 9.0 to 10.5) is necessary for effective cleansing and also to tie up calcium and magnesium ions found in natural waters and prevent them from interfering with the cleansing role of the detergent. Eutrophication is the progressive over-fertilization of water, in which festering masses of algae's blooms, choking rivers and lakes. Phosphorus compounds act as a fertilizer for all plant life, whether free-floating algae or more substantial rooted weeds, and are implica ...
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