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is the production of a group of genetically identical cells or organisms, all descended from a single individual. The members of a clone have precisely the same characteristics, except where mutation and environmentally caused developmental variation have occurre ....

Middle of Essay
.... are cut from a plant and placed in a flask with a nutrient medium. The cells grow and divide, forming embryonic tissues that are transferred to soil, where they produce complete plants. Grafting is another method of cloning used in Horticulture. Matching cuts are made in the stems of two plants, which are then fitted together so that their transport systems are in contact. The wounded area heals, and the two stems become a single physiological unit. All the McIntosh apple trees now in use and many other fruit varieties have been derived by grafting from single ancestral trees. "Nuclear transplantation," in which nuclei from cells of one individual ....