1. Cell Differentiation Stem cells have the potential to become any
type of specialized cell.

3. Want to know how this happens?

4. Within a few weeks after fertilization, stem cells
become committed to develop into only one type
of cell (cell determination).
Example: stem cell  neuron

5. Committed cells acquire the structures and
functions of specialized cells
(cell differentiation).

6. Committed cells retain all of the genetic
information.
During determination they loose their ability to
express some of this information.
Differentiation occurs because only specific
genes are turned on and off.

7. Committed cells retain all of the genetic
information.

8. During determination they loose their ability to
express some of this information.
Gene Expression

9. Differentiation occurs because only specific
genes are turned on and off.

10. Do you know what a TERATOMA is?

11. Teratoma: A tumor
made up of a tissues that come form all three germ layers
contains various kinds of embryonic tissue, such as hair , teeth, muscles,
bone and in rare cases organs such as eye, torso, hands, feet, or other limbs
can be created in the lab by injecting stem cells into mice
can be used to study cell differentiation

12. Teratoma tissue

13. Embryoid Bodies spherical colonies of cells resembling embryos
cultured from embryonic stem cells in the lab
after several days cells start to differentiate
cells begin to a limited extent to recapitulate embryonic development
serve as a good model to study early embryonic cell diferentiation