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I don't think many will be able to understand the subtleties of the argument. What is the difference between a blastocyst, a zygote, an embryo and a foetus, for example?
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Sperm and egg combine to produce a zygote, which is a single cell. That zygote divides, forming early on a blastocyst, which has about 150 cells. The blastocyst then moves to the endometrium, where it is implanted, about a week after fertilization.
An embryo is the organism from zygote to age two months. A fetus is the organism from two months to birth.
Cloning a blastocyst bypasses the stages of fertilization, conception, and zygote. Technically no zygote is produced.
The Bush administration has yet to take a position on this question, as far as I know.