Presentation on theme: "Stem Cells. Cell Differentiation and Stem Cells Major Topics for Discussion: 1) What are Stem Cells? 2) What are the major types of Stem Cells and where."— Presentation transcript:
Cell Differentiation and Stem Cells Major Topics for Discussion: 1) What are Stem Cells? 2) What are the major types of Stem Cells and where are they found? 3) Advantages & Disadvantages to ESCs and ASCs 4) Why are Stem Cells so very important? 5) The Controversy over Stem Cells? 6) What are the new advances in stem cell research?
What is cell differentiation? When unspecialized cells develop into specialized cells All cells have the same DNA but different genes are turned on in different cells. Also a cell’s location determine what it will become
Plants vs animals Animal cells can migrate to different areas but plants cannot. Outer layer becomes skin and nervous system. Middle layer becomes bones and muscles. Inner layer forms internal organs.
However, plants continue to develop all of their lives.
What are Stem Cells? Stem Cells are extraordinary because: They can divide and make identical copies of themselves over and over again, self- renewal Remain Unspecialized with no ‘specific’ function or become.... Specialized (Differentiated) w/ the potential to produce over 200 different types of cells in the body.
Adult stem cells have been found in many organs and tissues, including brain, bone marrow, blood vessels, skeletal muscle, skin, teeth, heart, corneas, liver, ovaries, and testis.
Go GGo Go Stem Cells! to see how adult stem cells work http://learn.genetics.utah.edu/content/tech/stemcells/sctypes/
Stem cells are classified According to their potential to develop into other types of cells. Embryonic stem cells can develop into almost any type of cells but adult stem cells only give rise to closely related cells.
Stem Cell Classification: Totipotent stem cell – can grow into any type of cell…only in fertilized egg or very early embryos (5- days) Pluripotent stem cell – can give rise to almost any cell…in early embryonic cells Multipotent stem cell – adult stem cell, only gives rise to closely related cells
Pluripotent Stem Cells – more potential to become any type of cell
Multipotent stem cells Multipotent stem cells – limited in what the cells can become
Advantages and Disadvantages to Embryonic and Adult Stem Cells. Embryonic S.C.Adult S.C. “Pluripotent” (can become almost any cell) “Multipotent”“ (can become many but not all) Stable. Can undergo many cell divisions. Less Stable. Capacity for self-renewal is limited. Embryo is destroyed.Difficult to isolate in adult tissue but not a moral issue
Growing an organism’s own stem cells Somatic Cell Nuclear Transfer or Therapeutic Cloning
1) Transfer nucleus from a mature cell into a donor egg whose nucleus has been removed. 2) Stem cells isolated from blastocyst to be induced to form needed tissues
Ideal because could use recipient’s own nuclei to build tissues
Why is Stem Cell Research So Important to All of Us? Stem cells can replace diseased or damaged cells Stem cells allow us to study development and genetics Stem cells can be used to test different substances (drugs and chemicals)
Technical Challenges Source - Cell lines may have mutations. Delivery to target areas Prevention of rejection Suppressing tumors
Why the Controversy Over Stem cells? Embryonic Stem cells are derived from extra blastocysts that would otherwise be discarded following IVF. Extracting stem cells destroys the developing blastocyst (embryo). -Questions for Consideration- Is an embryo a person? Is it morally acceptable to use embryos for research? When do we become “human beings?” Teachers' Domain: Stem Cells: Seeds of Hope?
Current research New Research points to a new direction in Stem Cell Research Teachers' Domain: Stem Cells Breakthrough