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Stem Cells. What are Stem Cells?. What are Stem Cells?. Stem Cells: Cells that do not yet have a specific function or job in the organism. . Where do we get Stem Cells?. Where do we get Stem Cells?.
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What are Stem Cells? • Stem Cells: Cells that do not yet have a specific function or job in the organism.
Where do we get Stem Cells? • Adult Stem Cells (multipotent): found in bone marrow, circulating blood, baby teeth, and umbilical cord blood.
Where do we get Stem Cells? • Adult Stem Cells: Harvested from living persons with their permission and without any harm to the donor.
Where do we get Stem Cells? • Embryonic Stem Cells (pluripotent): Found in a developing human embryo, 3-5 days after fertilization when it is about 150 cells big. Stem cells are found inside this cluster.
Where do we get Stem Cells? • Embryonic Stem Cells: Donated by fertility clinics. These unused embryos are donated with the couple’s knowledge and consent.
Why do we want Stem Cells? • Stem cells are currently used to treat over 70 diseases including leukemia, breast cancer, anemia, and some immune diseases.
Why do we want Stem Cells? • In the future, stem cells may also be able to treat Parkinson’s, Alzheimer’s, stroke, diabetes, spinal cord injuries, heart disease, and burns.
Why do we want Stem Cells? • Many public figures are in support of stem cell research.
Why the Controversy? • Adult stem cells (multipotent) • Pros: No harm to donor when they are collected • Cons: only have the potential to become about 10 different types of cells and they may be rejected by the recipient.
Embryonic stem cells (pluripotent) • Pros: Scientists believe that pluripotent cells can be developed into any of the 200 types of cells with little chance of rejection by the recipient.
Embryonic stem cells (pluripotent) • Cons: Using embryonic stem cells involves removing the stem cells from the embryo, destroying the embryo before it can develop.
Therapeutic Cloning • Combines cloning with embryonic stem cell therapy. • The nucleus from a cell of a person with a disease or injury, like a spinal cord injury, is cloned. • Then 3-5 days later, the embryo growth is stopped and the embryonic stem cells are used to fix the injury or disease.
Pros: cells are pluripotent, no waiting on transplant lists, and little chance of rejection because it is their DNA • Cons: the embryo is destroyed
Government Guidelines • Government funded embryonic stem cell research is currently allowed, but only if the couple has given consent to use the extra embryos from IVF treatments. • New embryos may not be created just to be researched. No therapeutic cloning
Homework • Stem cell research and funding, especially of embryonic stem cells and therapeutic cloning can be a political and controversial topic. • Take the survey form to see what you think, and then interview your family members about what they think • You may have to teach them what stem cells are before they can answer.
What does your family think? Should the US continue to allow research and/or funding on embryonic stem cells?
What do you think? 2. Should the US continue to allow research and/or funding on embryonic stem cells? 3. Should cloning be allowed on humans to further advance stem cell research? (The stem cells would be taken from the embryo 3-5 days after fertilization and the clone would not be born.)