1. Cell Differentiation Sexual reproduction (Meiosis) leads to a single fertilized cell and that cell has the ability to rapidly reproduce and allow the resulting cells to then differentiate into some specific cell type (via chemical signals)

2. Cell Differentiation The differentiation process is the result of the expression of certain specific genes but not others. DNA carries all possible expressions for any cell type; therefore, each cell contains all the genetic information necessary for the production of the complete organism

3. Stem Cells Cells that retain their ability to divide and differentiate into various cell types When stem cells divide to form a specific type of tissue (which is determined by the need of the organism) they also produce some cells that remain as stem cells which allows for the continual production of a particular type of tissue Stem cells look like normal cells (lifespan ~ 14 days)

4. Examples of stem cells include embryonic, umbilical cord of newborn, bone marrow Stem cells are being tested and may be used in the future to do the following: – implant stem cells in the brain to rebuild cells destroyed by Parkinson’s or Alzheimer’s – implant stem cells into the pancreas of people with certain forms of diabetes – Implanting into vertebrae to promote growth of bone tissue for people with chronic pain

6. Videos HANDOUT http://learn.genetics.utah.edu/content/tech/s temcells/scintro/ stem cell animation – learn genetics http://learn.genetics.utah.edu/content/tech/s temcells/scintro/ http://www.pbs.org/wgbh/nova/body/stem- cells-breakthrough.html stem cell videohttp://www.pbs.org/wgbh/nova/body/stem- cells-breakthrough.html