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How can Science and Technology Help and Hurt Humanity ?
How is Cloning Done?
• Many people first heard of cloning when Dolly the Sheep showed up on the scene in 1997. Artificial cloning technologies have been around for much longer than Dolly, though. • There are two ways to make an exact genetic copy of an organism in a
lab: artificial embryo twinning and somatic cell nuclear transfer.
What is Artificial Embryo Twinning?
A very early embryo is separated into individual cells, which are allowed to divide and develop for a short time in the Petri dish. The embryos are then placed into a surrogate mother, where they finish developing. Again, since all the embryos came from the same fertilized egg, they are genetically identical.
What is Somatic Cell Nuclear Transfer?The nucleus and all of its DNA are removed from an egg cell. Then they transfer the nucleus from the somatic cell to the egg cell. After a couple of chemical tweaks, the egg cell, with its new nucleus, was behaving just like a freshly fertilized egg. It will develop into an embryo, which will be implanted into a surrogate mother and carried to term.
What are Stem Cells?
Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells.
*They offer much hope for medical advancement because of their ability to grow into almost any kind of cell.
*For instance, neural cells in the brain and spinal cord that have been damaged can be replaced by stem cells.
*In the treatment of cancer, cells destroyed by radiation or chemotherapy can be replaced with new healthy stem cells that adapt to the affected area, whether it be part of the brain, heart, liver, lungs, or wherever.
Class Debate (part 1)
Point: Cloning is dangerous and should never be used.
Counter-Point: Cloning is safe and the benefits far outweigh the risks.
Class Debate (part 2)
Point: Stem cell research is a safer alternative to cloning.
Counter-Point: Stem cell research is still cloning and should be avoided at all costs.
