Final answer:
In reproductive cloning, the genome of the cloned individual is taken from the donor organism's somatic cell. This process involves nuclear transfer to an enucleated egg cell, resulting in an organism that is genetically identical to the donor. The first successful example was Dolly the sheep, but cloning continues to face technical challenges and ethical debates.
Step-by-step explanation:
In the reproductive cloning of an animal, the genome of the cloned individual comes from the donor organism from which the nucleus is taken. This method, known as reproductive cloning, is used to make an exact genetic replica of the donor organism. Unlike natural sexual reproduction, which combines DNA from two different parents, reproductive cloning bypasses this hybridization process by using nuclear transfer technology.
The process involves removing the nucleus from an egg cell and replacing it with a nucleus extracted from a somatic cell of the donor organism. This creates a new zygote that is genetically identical to the donor. The success of cloning Dolly the sheep in 1996 marked a significant advancement in this field. However, the cloned individuals, which include species like horses, bulls, and goats, often present some abnormalities, and there are ongoing ethical debates regarding therapeutic and reproductive cloning.
While therapeutic cloning focuses on creating embryonic stem cells for treating diseases, reproductive cloning aims to replicate entire organisms. The challenges, such as low success rates and potential impacts on the longevity and health of cloned animals, demonstrate the complexity and controversy surrounding this technology in modern biotechnology.