Word: physarum
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...life is protoplasm, the basic stuff of living cells. An intriguing characteristic of all raw protoplasm is its "streaming"-a flow like watery jelly. For some years Dr. William Seifriz, professor of botany at the University of Pennsylvania, has cultured an exceedingly primitive, golden yellow slime mold called Physarum polycephalum, just about the lowest observable form of life. In its streaming he has clocked a major rhythm of about 45 seconds (TIME, Dec. 6, 1937). Rather like a primordial heartbeat, this pulse may be the ancestor of all real heartbeats...
When Kamiya had seen with his own eyes the rhythmic throb of Physarum, a question leaped into his mind: "What is the horsepower, what is the amount of force involved?" To find out, he devised a new experiment. To perform it, he takes a little piece of the mold, works it into a sort of dumbbell shape-two blobs connected by a thin strand. He puts this into an air chamber divided into two compartments by a block of agar (marked C in the diagram). The two blobs, a and b, are in separate chambers but are connected...
...excite the admiration of Seifriz, who exclaims: "Did you ever see such perfect curves? Nothing like it has ever been done before. It makes biology an exact science!" Furthermore, Kamiya has noted definite changes in the wave forms and amplitudes of his curves. This he takes to mean that Physarum has not just one rhythm but several rhythms acting together. In other words the life throb of the slime mold is not just a simple drumbeat; it is an orchestration...
Last summer Dr. Seifriz overwhelmed with gratitude his friends at the Pasteur Institute by taking across the Atlantic a bowlful of Physarum polycephalum. Well might 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...
...primitive Physarum has extraordinary qualities of high resistance to X-ray bombardments and emanations from radium, it resembles the cells of stubborn cancers called fibrosarcomas...