1. Cell Membrane

2. Functions of the Cell Membrane
Gives shape
Maintain homeostasis
Regulates what goes in/out of cell (semi-permeable)

3. Cell Membrane Components
Outside
of cell
Inside
(cytoplasm)
Lipid Bilayer
Channel
Proteins
Protein
channel
Lipid bilayer

4. Cell Membrane Made of 2 layers of phospholipids
Phospho - comes from phosphorus
Lipids - fats
Bilayer – 2 layers

5. Parts of Phospholipid Tail (fatty acid) – repels water - hydrophobic
Head (phosphate) – attracts water - hydrophilic
Tail (fatty acid) –
repels water - hydrophobic

6. Channel Proteins
Control what goes in/out of cell

7. General Terms
Concentration Gradient – uneven distribution of particles
Turgor pressure – the water pressure in plant cells
Plasmolysis – Process where the cell membrane moves away from the cell wall due to water loss.

8. Passive Transport Movement of molecules that requires no energy
(high concentration low concentration)
Examples
1. Diffusion – movement from an area of high concentration to an area of lower concentration   
2. Osmosis – the diffusion of water
3. Facilitated Diffusion – movement of LARGE molecules through cell membrane via protein channels or carrier proteins

9. Diffusion vs. Passive Transport
Which side shows diffusion?
Which side shows passive transport?
High
Low

10. What determines movement of WATER?
the solute concentration in the solution that surrounds the cell

11. Isotonic Solutions
Found within our bodies

12. Active Transport Movement of molecules that REQUIRES energy.
Why does it require energy?
Because there is the movement of molecules against the concentration difference
(low  high) concentration

13. Passive and Active Videos
Passive Transport
Active Transport

14. 2 Types of Active Transport
Endocytosis – taking in material by infolding of cell membrane
Phagocytosis – “eating” of large particles; store food in a vacuole
Pinocytosis - taking in of liquids

15. 2 Types of Active Transport
2. Exocytosis – cell releases large amounts of material
-Label which diagram is endo/exocytosis

16. Exit Ticket 1. Please describe three types of passive transport.
2. Please compare and contrast endocytosis and exocytosis.
3. How do these types of endocytosis differ: phagocytosis and pinocytosis