.... tumors, or abnormal tissue, grow more rapidly than benign tissue and they invade normal tissue. Benign tissue is structured similar to normal tissue while malignant tissue is abnormal and has an unstructured appearance. Of greater importance, benign tissue does not metastasize, or begin to grow in other sites, like malignant tumors do. Cancer always refers to metastasized tumors but the term tumor is not always necessarily cancer. A tumor is any living tissue that is #1 distinguishable as abnormal living tissue. After a cancer forms, it can .....

.... the Earth's surface, gallium does not occor free or concentrated in independant minerals, except for gallite. It is extracted as a by-product from zinc blende, iron pyrites, bauxite, and germanite. Silvery white and soft enough to be cut with a knife, gallium takes on a bluish tinge because of superficial oxidation. Unusual for its low melting point ( about 30 degrees C, 86 degrees F ), gallium also expands upon solidification and supercools readily, remaining a liquid at temperatures as low as 0 degrees C ( 32 degrees F ). Gallium has the longest usefull li .....

.... radioactive isotope decays UV light: there were no protective ozone layer and thus immense heat. Electrical discharge from the never ending lightning caused chemical reactions to occur very often and there was also another source of heat from the young earth crust which was volcanically active. For most chemical reactions to take place, a spark of electricity is needed, and this was provided by the lightning in the atmosphere. Amino acids basically consist of hydrogen, nitrogen, oxygen and carbon. Due to all of the lightning chemical reactions took place betw .....

.... sometimes flew over 300 yards and was durable - until it got wet. Then it would split open. The Gutta percha was introduced in 1850 and was made of a rubberlike sap from the Malaysian sapdilla tree. The material was heated to soften it and then hand-formed into a solid, one piece ball.Gutta percha was black, so the early balls were painted white. Easier to make, less expensive, and more durable, the gutta revolutionized golf. When golfers discovered that balls and nicks flew longer and straighter then new ones, manufactures began to give them a textured, eve .....

.... difficult to do, are restricted to women over 35 and those who have a family history of chromosomal abnormalities. Prenatal tests using Willard's probes would be much simpler and faster to perform and could be available to all pregnant women who wish to take advantage of the technology. Current prenatal testing involves growing fetal cells in vitro and examining them, over one or two months, to see if there are two copies of a particular chromosome, which is normal, or one or three, which is abnormal. A test using Willard's probes would require only a .....

.... when scientists in Sweden and Norway first believed that acidic rain may be causing great ecological damage to the planet. The problem was that by the time that the scientist found the problem it was already very large. Detecting an acid lake is often quite difficult. A lake does not become acid over night. It happens over a period of many years, some times decades. The changes are usually to gradual for them to be noticed early. At the beginning of the 20th century most rivers/lakes like the river Tovdal in Norway had not yet begun to die. However by 1926 local .....

.... Electrons occupy energy states. Each level requires a certain amount of energy. For an electron to move to a higher level, it will require the right amount of energy. Electrons can move between different levels and between different materials but to do that, they require the right amount of energy and an "empty" slot in the band they enter. The metallic conductors have a lot of these slots and this is where the free electrons will head when voltage (energy) is applied. A simpler way to look at this is to think of atoms aligned in a straight line (wire). if we ad .....

.... the beginning of cell division and reappear at the end. Then you have the Cytoplasm. This is the watery material lying within the cell between the cell membrane and the nucleus. The Cytoplasm also contains organelles, which have specific functions in the cell metabolism. Then there are the Golgi Bodies, which serve as processing, packaging, and storage for the cell. These organelles package and ship things out. Another parts of the cell, a very important one in fact, are the Lysosomes. These organelles are used to break things down and contain enzymes. First we p .....