.... Africa south of the Sahara, particularly the Serengeti National Park in Tanzania and the Kruger National Park in South Africa. This drastic reduction in range came about as humans and domestic livestock spread into savanna lands. Because live in open areas, they are easily shot by hunters and herders. fur coats are a highly prized possession by poachers, and are worth a lot. Over the last 200 years, over 90% of the world’s lion population has either been shot or killed as result of humans. are also a very popular attraction for zoos and many live in captivity. Diet & Predatoria .....

.... Sea water contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tons of sea water contains 4.6x10^9 tons of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in sea water for 7 million years(Energy 25). This is a only a theoretical number because it is not possible to get all of the uranium out of our vast oceans. Also, it does not include the fact that in that many years, half of the uranium will no longer exist due to radioactive decay. So, at worst, we would get about 2 million years of power from it. Thorium is anoth .....

.... and sometimes so simple. There are two different kinds of causes that drastically cut Down the number of these endangered species: Direct Causes Direct Causes is when the animals are purposely hunted, trapped, fished, whaled, or seled to extinction. Hunting for sport has been responsible for endangering such animals as the Polar Bear and the Siberian Tiger. But the endangerment of most species that are hunted or trapped today results mainly of commercial activities. Among the animals that have become endangered for commercial reasons are several species of whales, including the enormous .....

.... or completely shut position. This type of valve is used where flow rates are not restricted. Globe valves are the second most common valve used I industry. A globe valve places a movable metal disc in the path of a process flow. This type of valve is most commonly used in the throttling service. Ball valves take their name from the ball-shaped, movable element in the center of the valve. The movable ball rotates to let flow pass through, and closes to stop it. Ball valves are not made for throttling service. Check valve is a type of automatic valve designed to cont .....

.... you need to make a good impression on. Be it with a teacher, someone who is interviewing you for a job, or simply someone you are trying to get romanticly involved with. Then there are the more harmful and insidious side effects of smoking. Such as lung cancer, cancer of the throat, and other health problems too numerous to mention. Lung cancer has become very common amoung smokers and it is known fully by most smokers that they are getting cancer sooner or later as long as they continue to smoke as if it is an ineviatble fate. This is not only so to the smoker but the second hand smoke t .....

.... site. Recent studies of enzyme structure have suggested that the active site is flexible. The binding between and substrate appears to alter the shape of the enzyme. This induces a close fit between the active site and the substrate. It is also believed that this may put some strain on the substrate molecule facilitating the reaction. Another characteristics of are competitive inhibition and non-competitive inhibition. Competitive inhibition is the binding of a competitive molecule to the active site of the enzyme. This prevents the proper substrate from reacting with the enzyme. .....

.... did not stop to think of the ramifications of his accomplishment. The ethical dilemma was not explored before hand, and this to me is the great tragedy of most scientific discovery, since I firmly believe each scientist is responsible for that which he creates. Djerassi does confront a few questions of ethics and morality after the fact. On page 61, in chapter 6, he reflects on the argument of the use of poor Mexican and Puertorrican women for preliminary experiments. Is this just another manifestation of exploitation of the poor? Djerassi says absolutely not. Yes, the poor our the .....

.... from willow tree to Nobel Prize Aspirin's active ingredient, acetylsalicylic acid (ASA), is the commercially synthesized form of a naturally occurring compound whose uses can be traced back 2,000 years. The compound, called salicin, is found in the white willow tree. Around 200 B.C., Hippocrates, the Greek physician, discovered that chewing on willow bark could relieve pain and fever. Although ASA was a proven pain reliever, no one really knew how it worked until more than 70 years after Hoffmann's discovery. In 1971, British pharmacologist John Vane discovered that the anti-inflammat .....

.... solidifies. Allotropes are different forms of the same element. For Example, oxygen has two allotropes, normal oxygen and ozone. Pure carbon also has two allotropes, diamond and graphite. A crystal of diamond is in fact a single giant molecule in which every carbon atom is linked to four other, by four equal, strong bonds. These bonds are arranged tetrahedrally round each atom and there are no planes along which the giant molecule can easily be split. This quality is what gives diamond its tremendous hardness. Graphite on the other hand, consists of flat sheets of carbon atoms arran .....

.... response as well. Paraheliotropism minimizes water loss by reducing the amount of light absorbed by the leaves; the leaves orient themselves parallel to the sun’s rays. Plants that exhibit paraheliotropic behavior usually do so at midday, when the sun’s rays are perpendicular to the ground. This reorientation takes place only in leaves of plants that are capable of nastic light-driven movements, such as the trifoliate leaf of Erythrina spp. (Herbert 1984). However, this phenomenon has been observed in other legume species that exhibit diaheliotropic leaf movement as well. .....