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Have you heard of cloning? It's the process of making an exact genetic copy of an organism.
Some organisms, such as bacteria, many plants like sugarcane, and simple animals like starfish, naturally clone themselves through asexual reproduction, but most animals cannot.
In 1997, scientists successfully created Dolly the sheep, the first mammal to be cloned from an adult cell.
To create her, scientists took a cell from an adult sheep’s udder and removed its nucleus, which contained the DNA to be copied.
They also took an egg cell from another female sheep and removed its own nucleus.
The nucleus from the udder cell was then inserted into the empty egg cell, and an electric shock helped fuse them together, triggering it to divide.
The resulting embryo was then placed into a surrogate sheep, and Dolly was born.
Since the nucleus came from the adult sheep, Dolly inherited all her DNA from that sheep, not from the egg donor or the surrogate.
Because she was the only success out of 277 attempts, cloning remains difficult and is now mainly explored for medical research and conservation.
