1. Section 3: Cell Transport

2. I. Cell Membrane Cell membranes are made of phospholipids bilayer.
Semipermeable- they allow some but not all materials to enter and exit the cell
Provides a barrier that separates the cell from the external environment.
Aides in protection and support.
Aides in communication between other cells.

3. II. Cell Membrane Structure:
1. Phospholipids=
Phosphate Head= Hydrophilic
Fatty Acid Tail= Hydrophobic
(soluble or not soluble?)
Interacts with water!

4. II. Cell Membrane Structure:
Proteins= In phospholipid bilayer to act as a gate or channel for things that are to big to go threw phospholipids
Carbohydrates= Attached to some protein channels as long carbohydrate chains to serve as ID cards of the cell; allowing the cell to communicate and recognize other cells.

5. III. Cell Transport Movement Across the Plasma Membrane
A few molecules move freely
Water, Carbon dioxide, Ammonia, Oxygen
Carrier proteins transport some molecules
Proteins embedded in lipid bilayer
Fluid mosaic model – describes fluid nature of a lipid bilayer with proteins

7. III. Cell Transport There are 2 kinds of transport in cells:
1. Passive Transport= movement of substances without requiring any energy to be put in. Moves from High Concentration to Low Concentration [ ] [ ]
Diffusion= The movement of molecules from areas of high concentration to low concentration (from areas of lots of stuff to areas of not so much stuff)
Facilitated Diffusion= movement of large molecules through protein channels
Osmosis= a type of diffusion that involves the movement of only WATER.

8. III. Cell Transport There are 2 kinds of transport in cells:
2. Active Transport= movement of substances WITH requiring energy to be put in.
Uses energy in the form of ATP.
Moves from Low Concentration to High Concentration [ ] [ ]

9. THE END!

10. Next: We are going to do a lab activity over diffusion and osmosis.
First, take ten minutes and read the whole thing then answer the Pre-lab and experiment questions.
You make work in groups.

11. Quick Quiz
What is the difference between a eukaryote and a prokaryote?
What are the differences of a plant cell versus an animal cell?
What does active transport need that passive transport does not?