oduced is a clone (McKinnell 6).
The essential fact of sex in both plants and animals, that hereditary material from two individuals is joined to form a new creature. The sex cells provide diversity so that each offspring produced is unique in its combination of traits. Cloning does not involve sexual reproduction, and so the cloned plant is not the result of a union of different material. The plant produced by cloning is a manifestation of the capacity for new growth of the old plant body, so the new plant is usually genetically identical to the old plant. Cloning is used in agriculture to produce high-quality, uniform products (McKinnell 6-7).
Cloning of animals is less common, but there is a procedure well established for permitting asexual reproduction in amphibians such as toads, frogs, and salamanders. This procedure is known as nuclear transplantation and is widely referred to as cloning. Frogs were the first multicellular animals cloned because they have an abundant supply of eggs and sperm that experimenters can use. The fertilization and embryonic development of the frog ordinarily takes place outside the animal's body in ponds, and so it is more easily accomplished in the laboratory in glass dishes, a method which permits direct observation of and experimentation with all stages of development. Experiments in the late nineteenth century on frogs provided the groundwork for cloning (McKinnell 9-10).
The method used a decade ago for the successful nuclear transplantation in amphibians required that the egg be enucleated, which meant removing the maternal hereditary material contained in the egg nucleus. Other hereditary material contained in the nucleus from a body cell would then be placed in the enucleated egg, and the resulting clone would be parentless:
Biologically, a mother is a mother by virtue of the fact that she contributes hereditary material via the chromosomes of an egg. . . a father is a b...