.... For example, sucrose is the substrate for the enzyme sucrase. have specific structures that only its specific substrate will fit into. The polypeptide chains of an enzyme are folded in such way that they form a grove or pocket on the surface. The substrate fits in to this grove, which is the site of reactions catalyzed by the enzyme, or active 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 ....

.... and residential fuel combustion together contribute most of the rest. In the air, the sulphur dioxide and nitrogen oxides can be transformed into sulphuric acid and nitric acid, and air currents can send them thousands of kilometers from the source. When the acids fall on to the earth in any way or form it will have a large impact on the growth or the preservation of certain wildlife. Areas in Ontario mainly southern regions that are near the Great Lakes, such substances as limestone or other known antacids can neutralize acids entering the body of water thereby protecting it. However, large areas of Ontario that are near the Pre-Cambrian Shield, with quartzite o ....

.... divides the oxygen molecule (O2). Each molecule then attaches with other oxygen molecules to form O3. O3 is ozone. So when ozone is formed, harmful rays from the sun are absorbed. The O3 molecule is very reactive and it bonds easily with other molecules it the atmosphere. When and oxygen atom from the ozone reacts with a chloride ion from chlorine monoxide, the ozone molecule is destroyed. So chlorine monoxide is an ozone destroyer. There is always a certain amount of chlorine monoxide in the atmosphere. It is important to remember that ozone is constantly being created and destroyed in the atmosphere. The amount of ozone in the atmosphere is based on these reactions. The ....

.... to process our shorthand dates correctly. Some of these computer systems will produce obviously silly results, good for a laugh at the office. Some will produce subtle errors that may be passed on, undetected at the source, in an ever-expanding circle of bad data. And some systems will stop working altogether. How might systems fail? Let's look at an example program in which the omitted century is assumed to be '19' and the program's function is to figure out how old you are. If you were born in 1958, then in 1999 this program will calculate your age as 99 minus 58, or 41. That's fine, but what happens when the century rolls over to '20' in the year 2000? In this progra ....

.... is also called the "preying" mantis because of its predatory nature. CLASSES Many questions have risen regarding the praying mantis. Such questions include how many different species there are in the animal kingdom. Estimates range from 1500 to 2200 different mantid species WORLDWIDE. The most common figure given, though, is about 1800. The ways the Mantid's are classified in the Animal Kingdom. There is agreement that the collection of mantid species make up the Mantidae family of insects. The Mantidae family, in turn, is part of the order/suborder Mantodea that includes a variety of mantid-like species. But the existing literature does not reflect a clear consensus ....

.... U.S. The disease is . is a group of rapidly reproducing, undifferentiated cells in the area of the breast in women. The earliest changes occur in the epithelial cells of the terminal end buds (TEB) of the breast milk ductal system. While the outlining steps of are unknown, the cells in the breast trigger a reaction of cell reproduction. These new cancer cells form tumors. If cancer cells are active or are considered malign, the tumor grows at tremendous speeds, and may end up in metastasis. Metastasis is a complex process in which cells break away from their primary tumors, and via the blood supply or through the lymph system relocate into other organs, thus spreading ca ....

.... if you want an easy way into the chemistry field you need to know someone already in that occupation. For the most part in Missouri, employment is increasing. Nevertheless, if you are not restricted to finding a job in Missouri, in the United States a whole employment is expected to increase 21% (Choices). After finding a job in the chemistry field that you will enjoy another quesiton arises, money. On hte average if you begin working at a entry level job witha bachelors degree your salary will be somewhere around $24,000 a year. If you start work with a masters degree you can expect about $32,000 and with a Ph.D. as mcuh as $60,000 ("Chemists") Research and d ....

.... of DNA duplication is known as replication. The hydrogen bond between the base pairs of the 2 nucleotide strands weaken, and the 2 strands break apart. Each strand acts as a template forming a new nucleotide. This is accomplished by the acting of 2 sets of enzymes - DNA helicase enzymes and DNA polymerase enzymes. The DNA helicase enzymes separate the 2 nucleotide strands. The site where the helicase is working and where replication is taking place is known as the DNA fork. The polymerase enzyme helps the nitrogenous base in a given nucleotide to pick up and attach to a complementary base at the 3' end of the DNA template. The 5'-3' strand of template is duplicated in short ....