What is the difference between adult cells and embryonic cells?
- Embryonic stem cells come from a few days old embryo, which is normally destroyed to remove them. While adult stem cells are the reservation that are created in every organ and tissue of the body during the development.
They have the natural function of regenerating injuries to the body and are already used to cure degenerative diseases or injuries to the spinal cord or heart.

Can science advance without using embryonic cells?
The research with cells from embryos has given rise to very valuable knowledge. But the end does not justify the means. By possibly slower routes, the same data would have been achieved by extrapolating from animal experimentation. Three years ago, the Japanese scientist Yamanaka created, with extraordinary scientific and ethical rigor, the reverse path to achieve cells in a pluripotent state similar to embryonic ones: he rejuvenated mature adult cells. To check to what extent they were the same or similar to those from embryos, he refused to produce them by destroying embryos. He did all the tests with mice.