(This series of posts reviews in detail Francis Collins’s book The Language of God: A Scientist Presents Evidence for Belief, originally published in 2006. The page numbers cited are from the large print edition published in 2007.)
In the Appendix of his book The Language of God: A Scientist Presents Evidence for Belief (2006), Francis Collins gives a very clear and brief exposition of the issues involved in stem cell research and cloning, which are not the same thing despite popular impressions.
A human being starts out as a single cell formed by the union of an egg and a sperm. The nucleus of this cell contains the contributions of DNA from each of the two parents and thus all the genetic instructions, while the region outside the nucleus, called the cytoplasm, contains the nutrients and signaling mechanisms that enable the cell to do whatever it is meant to do.