1. Specialized Cells and Cell Differentiation

2. Do all cells look the same?
Animal Cell
Plant Cell

3. Cell Specialization
Different cells do different tasks in animals and plants
Example: muscle cells different than blood cells
Cells in leaves different than cells in roots
If cells do different tasks, how will they differ from each other?

4. Cell Specialization
Specialized cells have the following to help do their specific jobs:
Specific shapes
Specific sizes
Specific organelles
In general, they have different physical and chemical properties

5. Cell Differentiation
TWO things must happen during Cell differentiation
stem cells receive chemical signal to turn into specialized cells
Only a portion of the cell’s DNA (i.e. genes) is activated to turn a cell into a specialized cell
( that is, one set of genes is turned on in one cell type while another set of genes is turned on in another cell type)
Not all genes are turned on in any given cell
One set of genes is turned on in one cell type while another set of genes is turned on in another cell type.

6. Examples of Specialized Cells
Red blood cells
Smooth membrane and rounded shape to pass easily through blood vessels
Thin membrane that allows O2 to enter and CO2 to exit

7. Examples of Specialized Cells
Muscle cells
Long cells
arranged in parallel bundles to contract
Contain many mitochondria for energy

8. Examples of Specialized Cells
Sperm Cell
Tail used for movement
Many mitochondria for energy
Nucleus/DNA located in the head where sperm enters the egg

9. Examples of Specialized Cells
Leaf cells
Thick cell wall to prevent H2O loss
Lots of chloroplasts to capture sunlight and make sugars
Guard cells 

10. In Conclusion...
Structure-function Relationship: Specialized cells have a specific physical form (structure) that helps them perform their job (function)
Although all cells have the same DNA, only a part of the DNA is activated to produced a particular type of specialized cell