.... it condensed into galaxies. The universe has continued to expand, and the galaxies have continued moving away from each other ever since. Today the universe is still expanding, as astronomers have observed. The Steady State model says that the universe does not evolve or change in time. There was no beginning in the past, nor will there be change in the future. This model assumes the perfect cosmological principle. This principle says that the universe is the same everywhere on the large scale, at all times.2 It maintains the same average density of matter forever. There are observational evidences found that can prove the Big Bang mo .....

.... The virus is a member of a family of RNA viruses know as filoviruses. Marburg virus and four viruses: Zaire, Sudan, Reston and Tai are the five different viruses that have been known to cause disease in humans, while Reston only causes disease within monkeys. Filoviruses, arenaviruses, flaviruses, and bunyaviruses are the viruses responsible for causing viral hemorrhagic fevers. All forms of virus of viral hemorrhagic fever begin with fever and muscle aches. These diseases usually progress until the patient becomes very ill with respiratory problems, severe bleeding, kidney malfunctions, and shock. The conclusions of the viral hemorrhag .....

.... leave it alone and do not harm it, it might have baby’s and have more of its kind. A species is named endangered when of its kind occurs in a low number. About 1000 species in the world are named endangered, or are in threat to be extinct. I never knew that some kinds of birds were in danger. We can help these animals and plants by making laws that you are not allowed to hunt or kill any animal that is in danger of extinction. Government Involvement Only since the 19th century has there been worldwide concern about the case of species in their natural environments. Finally in 1916 they made a law called Migratory Bird Treaty. They had this la .....

.... hormones and other biological compounds used to treat human diseases. For example, bacteria can produce the hormone insulin, which is used to treat diabetes. Such uses of transgenic organisms are widely referred to as genetic engineering. Transgenic organisms have proved very useful in analyzing the function of gene products because a specific gene can be expressed in all the cells of a transgenic organism and the effect on the organism's development and function can then be monitored. It is also possible to use transgenic procedures to produce animals in which a specific gene has been deactivated in all its body cells. Certain genetic di .....

.... cluster are only 300,000 years old. The is an emission nebula because of the O-type and B-type stars contained within it. These high-temperature stars emit ultraviolet (UV) light that ionizes the surrounding hydrogen atoms into protons (H+) and electrons (e-). When the protons and electrons recombine, the electrons enter a higher energy level (n=3). Then, when the electron drops from the n=3 level to the n=2 level, an Hphoton is emitted. 2 This photon has a wavelength of 6563 Ã…, and therefore corresponds to the red portion of the visible spectrum. It is these H photons which give the nebula the distinctive red color whic .....

.... have instituted experiments for producing gold from orpiment, a sulfide of arsenic, and the emperor Diocletian is said to have ordered all Egyptian works concerning the chemistry of gold and silver to be burned in order to stop such experiments. Zosimus the Theban (about AD 250-300) discovered that sulfuric acid is a solvent of metals, and he liberated oxygen from the red oxide of mercury. The fundamental concept of stemmed from the Aristotelian doctrine that all things tend to reach perfection. Because other metals were thought to be less "perfect" than gold, it was reasonable to assume that nature formed gold out of other metals deep within the ea .....

.... From an early period the Egyptians possessed the reputation of being skillful workers in metals and, according to Greek writers, they were conversant with their transmutation, employing quicksilver in the process of separating gold and silver from the native matrix. The resulting oxide was supposed to possess marvelous powers, and it was thought that there resided within in the individualities of the various metals, that in it their various substances were incorporated. This black powder was mystically identified with the underworld form of the god Osiris, and consequently was credited with magical properties. Thus there grew up in Egypt the .....

.... known as coral bleaching. As mentioned earlier, coral reefs are among the most diverse and productive of all communities on Earth. They are also the largest biological structures on the planet. The Great Barrier Reef, along the eastern coast of Australia, covers over 2000 kilometers and is said to be visible from the moon (Goreau, 1987). While the size of coral reefs can be enormous, their real impact is on a much smaller scale. Reefs function as food and shelter for fish and marine invertebrates. While the coral itself is an animal, through a symbiotic relationship with the unicellular algae, coral becomes the primary producer in its ocean ecosy .....

.... the cells form a tumour. The crowded cells fail to stop dividing until they push everything out of place. If the tumour is benign it will enlarge only at the site where it began. However cancerous tumours can invade and destroy. One of the reasons that cancer needs to be caught early is because it will spread. Cancerous cells lack the sticky coating that causes normal healthy cells to stay together because cancerous cells lack it they can break off and implant somewhere else in the body. The cancerous cells that break off from the primary tumour are usually carried through the blood. What causes cancer cells to be abnormal? They create extra c .....

.... Union, a Masai village in Africa and Abilene, Kansas, which is located in the U.S. These three places are part of the world’s mid-latitude grassland region. Grasslands are usually found in the interior parts of most continents. The world’s grasslands are vast areas covered with grass and leafy plants. They generally have a dry climate, little vegetation, and most grasslands receive only about twenty to thirty inches of rain each year, with most of it coming in the same season. Some grasslands may even receive up to thirty to forty inches of rain a year! For example, since the grasslands of the United States have hot summers and mild winter .....