1. Cell Death Stem Cells Friday 15th August
‘Cells in Action’ Test is on Monday 18th

3. Cell Death
Two Types:
Necrosis (Cells are passive victims of oxygen deprivation or disease).
Apoptosis (Cells actively participate in own death – intentional suicide)

4. Necrosis
Is the uncontrolled, accidental, messy murder of useful cells that have been severely injured by an agent external (oxygen deprivation or disease) to the cell.

5. Roles of Apoptosis
Predictable self-elimination of selected cells is a normal part of development. E.g. elimination of webbing between fingers during development
Tissue turn over – maintains the proper number of cells in tissue (i.e. removes the old as the new cell are produced

6. Webbed Hands & Feet

7. Roles of Apoptosis
In the immune system removes cells infected with viruses and the infection-fighting white blood cells after they are no longer needed.
Removes undesirable cells (aged, damaged or mutated cells)

8. APOPTOSIS – ‘Programed Cell Death’
Scheduled or programmed cell death
internal enzymes are released to break down cell.
Dying cell is eaten or phagocytosed by special cells
This system removes excess tissue
Helps to shape organisms

9. Apoptosis & Disease
Many diseases and disorders are linked with the life and death of cells -- increased apoptosis is a characteristic of AIDS, Alzheimer's and Parkinson's disease, while decreased apoptosis can signal lupus or cancer.
Anti-cancer drugs and radiation, for example, work by triggering apoptosis in diseased cells.

10. STEM CELLS
Versatile cells that are not specialised for a particular function.
Can divide to develop into any specialised cell

11. Types: Embryonic: Somatic:
Result from early divisions (mitosis) of a fertilised egg
Are pluripotent (potential to generate more than 200 different types of cells)
Somatic:
Derived from adult tissue cells
Less versatile and less flexible.
Can develop only into a selected number of types of calls

12. Medical Potential of Stem Cells
Spinal Injuries
Alzheimer's Disease
Parkinson Disease
Insulin-dependent diabetes
Stroke

13. Cells in Action Revision
Revision Action Plan
Answers will be uploaded to Learning Areas (Make a serious attempt before you use these)