Cloning refers to the process of developing an embryo with the DNA from an adult animal.
Cloning may invoke an image of an army of identical cows or sheep churned out factory-style, but in actuality, the process is much more laborious.
The term "cloning" generally applies to a process more technically known as somatic cell nuclear transfer. What that means is that the DNA from the cell of an adult animal (take cows, for example), called the "donor," is extracted from the cell (usually a skin cell taken in a biopsy) and inserted into an egg cell from another cow. The egg cell has had its nucleus removed so that it will read and duplicate the DNA of the donor cell.
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