Colchicine, an alkaloid first extracted from the autumn crocus and later synthesized. The ability of colchicine to control acute attacks of gout has been known since the 1700s, but its mechanism of action is still being studied. Some patients taking colchicine develop serious diarrhea or have a greatly reduced number of white blood cells (see Blood). For these patients, one of the newer synthetic antigout agents is substituted. Because colchicine inhibits cell division, it is also a valuable laboratory tool for studying the structure of chromosomes.
Matter is composed of atoms or groups of atoms called molecules. The arrangement of particles in a material depends on the physical state of the substance. In a solid, particles form a compact structure that resists flow. Particles in a liquid have more energy than those in a solid. They can flow past one another, but they remain close. Particles in a gas have the most energy. They move rapidly and are separated from one another by relatively large distances.
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