Word: protoplasmal
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Dates: during 1930-1939
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Just 16 men are to appear, top-flight biologists and physicists all, at a symposium. In one room they will sit as on a sort of scientific Olympus, and each will make a formal statement of the most interesting truths he knows about biological cells and protoplasm. Then they will swap ideas and comments and, inevitably, some of them will, in the most abstruse scientific terms, call some others liars...
...Italian-born Physicist Gioacchino Failla, who is in charge of the physics and biophysics laboratories at Manhattan's famed Memorial Hospital, suggested a straight-forward physical theory for the lethal effect of X-rays. An electric charge passing through a cell, said Dr. Failla, divides the molecules of protoplasm into positively and negatively charged particles. These ions then recombine to form new chemical substances. In a vain attempt to re-establish osmotic equilibrium in the cell, water from the intercellular spaces flows into the cell through the membrane, causing the cell to swell...
Give a biologist a pinch of slime mold-primitive but living protoplasm-and he will have no difficulty predicating an evolutionary ascent, from that bit of animate substance, which leads to large, complex and reasoning beings like himself. Yet the prime question remains: How did the first bit of life appear on earth...
...This protoplasmic streaming interests Dr. Seifriz immensely. The movements of Physarum show a definite pulse, not unlike that of a beating heart. With inadequate motion-picture equipment at Philadelphia, he was not able to see this living rhythm until he went to studv at the Pasteur Institute in France where films had been made and slowed down 100 times. The Physarum pulse was seen to have a period of about 45 seconds. Dr. Seifriz rejects the older theories attributing protoplasmic movement to surface tension, electric potentials, etc. "I ask the reader," he wrote recently in Science, "merely to admit that...
...they be pleased with such a thing to study for this mold in many ways is the lowest visible form of life. Bacteria are smaller than the mold cells but their claim to superlative primitiveness is "questionable" and they are harder to study. Amebas are also simple bits of protoplasm, but they have something which Physarum lacks-a contractile vacuole (cavity) which squirts body fluids to the outside...