1. Clicker QUIZ!!
We will now have a quiz on the functions of each part of the phospholipid bilayer.

2. Passive Transport

3. Transport
The cell must move substances of varying size, electrical charge, and composition into and out of the cell.
In active transport across the membrane the cell uses energy.
In passive transport across the membrane the cell does not use energy.

4. Passive transport Equilibrium: when a space is filled evenly.
Concentration: the amount of a particular substance in a given volume.
Concentration gradient: when one area has a higher concentration than another.
Substances move from an area of high concentration to an area of low concentration.
Some substance enter and exit the cell by diffusing across the cell membrane.

5. Simple Diffusion
Small nonpolar molecules can pass directly through the lipid bilayer. (Simple diffusion)
Molecules must move down the concentration gradient.
Molecules which diffuse simply are nonpolar and fat soluble.
Diffusion can take place in both directions but with different molecules.
Ex: oxygen diffuses in as carbon dioxide diffuses out of the cell because two gradients are present in opposite directions.

6. BODY MIND TIME!!! Now we will learn motions for:
Concentration gradient
Diffusion
Equilibrium

7. Facilitated Diffusion
Facilitators in new tech help/assist
Facilitated basketball shot – assists the basket
During facilitated diffusion transport proteins help substances diffuse through the cell membrane.
Two types of facilitated transport proteins:
Channel proteins
Carrier proteins

8. Facilitated Diffusion Video

9. Transport Proteins Video

10. Channel Proteins
Ions, sugars, and amino acids can diffuse through the cell membrane through channel proteins.
These proteins aka pores serve as tunnels through the lipid bilayer.
Each tunnel allows for a specific substance to diffuse through it. This substance has a specific size and charge.

11. Channel – tunnel

12. Carrier Proteins- hand
Transport substances that fit within their binding site.
A carrier protein binds to a specific substance on a specific side of the cell membrane.
This binding causes the substance to change shape.
As the shape changes the protein is moved across the membrane and release on the other side.
This is enzyme activation across the membrane

13. Carrier – Hand

14. Channel and Carrier Proteins
Videos
Channel and Carrier Proteins

15. Osmosis Diffusion across a selectively permeable membrane.
Osmosis allows cells to maintain water balance as their environment changes.
(what is maintaining an internal environment called?)
Osmosis allows for water molecules to move down the concentration gradient to create an equilibrium between the cell and the external environment. – Basically the diffusion of H20

16. Water Channels
Polar water molecules do not diffuse directly across the bilayer.
The cell membrane contains channel proteins that only water can pass through.
Osmosis in cells is a type of facilitated diffusion.

18. Osmosis across a cell membrane
Osmosis Video
Osmosis in a beaker
Osmosis across a cell membrane

19. Activity
In class with a partner compare, contrast and create a chart for these passive transport methods.
Channel
Carrier
Osmosis
While you do it we can listen to these songs
Cell transport SONG
Osmosis Song with Mr. W.