Word: oxygenate
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Three planets were nominated as possible havens for such life. Nobel Chemistry Laureate Willard F. Libby speculated that oxygen detected on Venus by a Soviet space probe last October may well be the product of plant photosynthesis. Jupiter, said NASA Chemist Cyril Ponnamperuma, has an atmosphere similar to that which enveloped the earth during its first 100 million years; the swirling Jovian gases, he added, may already have combined into basic life-building molecules. But the strongest argument was made on behalf of Mars. Despite its freezing temperatures and apparent lack of oxygen, explained NASA Microbiologist Harold P. Klein, life...
...those three decades, Perutz discovered much of what is now known about the hemoglobin molecule, which he rightly calls "an incredible apparatus." Scientists have long known that hemoglobin in the bloodstream carries oxygen from the lungs to the body tissues and returns waste products from the tissues to be exhaled from the lungs. But not until Perutz learned how to put the pieces of his intricate puzzle together did anyone begin to understand just how hemoglobin does...
Each hemoglobin molecule, Perutz found, consists of 10,000 atoms, of which four are iron atoms that have an affinity for oxygen. In the lungs, in the presence of oxygen, the hemoglobin molecule changes shape, moving each of the four iron atoms, which are located in separate "pockets" on its surface, to different positions. This change increases by 300 times the molecule's attraction for oxygen atoms, pulling four of them into combination with the iron atoms. It is only because there are 280 million hemoglobin molecules in each red corpuscle that the blood has sufficient oxygen-carrying capacity...
...molecule delivers its oxygen to the body's tissues, it reverts to its original shape and attracts charged hydrogen atoms. The blood thus becomes alkaline, forms a temporary chemical bond with carbon dioxide and water from the tissues in the form of bicarbonate and carries it to the lungs, where it changes back into water and carbon dioxide before being exhaled. The change of molecular shape is important, says Perutz, "because it is the most elementary manifestation of the property of a living system that can turn chemical energy into movement...
These organic compounds made of carbon, nitrogen, hydrogen and oxygen resemble ordinary liquids. Yet their orderly molecular structure is similar to that of solid crystals such as diamonds, mica and quartz. The crystals themselves are not new, but it was only recently that scientists discovered that an electrical charge makes them light-reflecting; the higher the voltage, the greater the reflecting power. At first, this "electro-optical effect" could be shown only in the laboratory, since the crystals reacted to electricity only at certain temperatures. Now, after trying more than 100 compounds, RCA scientists have produced a crystal that responds...