1. Brainteaser
What has wheels and flies, but is not an aircraft)?

2. Study the diagram below
Study the diagram below. Which arrow shows the direction the solute molecules would move to achieve homeostasis?

3. If the membrane shown is permeable to molecules of X, but impermeable to molecules of Y, what will be the result of diffusion over time?
Molecules of X on each side of the membrane will become equal in concentration.
Molecules of Y on each side of the membrane will become equal in concentration.
Molecules of X will increase in
concentration on the right side.
Molecules of Y will increase in

4. Cellular Transport Osmosis

5. Today you will review Passive Transport Osmosis
Osmosis within the 3 types of solutions.

6. Types of Cellular Transport
high
low
Weeee!!!
Passive Transport
cell doesn’t use energy
Diffusion
Facilitated Diffusion
Osmosis
Active Transport
cell does use energy
Protein Pumps
Endocytosis
Exocytosis
high
low
This is gonna be hard work!!

7. 3 Types of Passive Transport
Diffusion – molecules move high to low.
Facilitative Diffusion – diffusion with the help of transport proteins.
Osmosis – Water moves high to low.

8. Passive Transport: 1. Osmosis
1.Osmosis: diffusion of water through a selectively permeable membrane.
Water moves from high to low concentrations.
Water moves freely through pores.
Solute (green) too large to move across.

9. Effects of Osmosis on Life
Osmosis- diffusion of water through a selectively permeable membrane.
There are 3 types of solutions:
Isotonic
Hypertonic
Hypotonic

10. Isotonic Solution
Solutions that contain the same concentration of solutes as the cytoplasm are called isotonic (or normal saline) solutions.
There is no net movement of water either into or out of the cell.
Cells maintain their normal shape.
WATCH VIDEO OF BLOOD IN AN ISOTONIC SOLUTION

11. Osmosis Animations for isotonic, hypertonic, and hypotonic solutions
Isotonic Solution
Isotonic: The concentration of solutes in the external solution is equal to the concentration of solutes inside the cell.
Result: Water moves equally in both directions and the cell remains same size! (Dynamic Equilibrium)

12. Hypertonic Solution
A hypertonic solution is a solution that contains more (hyper) solutes than the cytoplasm of the cell.
Has less water than the cell and
water moves out of the cell.
The cells shrink.
WATCH VIDEO OF NORMAL RBCs SUBJECTED TO A HYPERTONIC SOLUTION

13. Osmosis Animations for isotonic, hypertonic, and hypotonic solutions
Hypertonic Solution
Hypertonic: The solution has a higher concentration of solutes and a lower concentration of water than inside the cell. (High solute; Low water)
shrinks
Result: Water moves from inside the cell into the solution: Cell shrinks (Plasmolysis/crenation)!

14. Hypotonic Solution
A hypotonic solution contains less solute (thus, more water) than the cytoplasm of the cells.
The water will move into the cells resulting in the swelling and lysis of the cells. 
WATCH VIDEO OF CRENATED RBCs SUBJECTED TO A HYPOTONIC SOLUTION

15. Osmosis Animations for isotonic, hypertonic, and hypotonic solutions
Hypotonic: The solution has a lower concentration of solutes and a higher concentration of water than inside the cell. (Low solute; High water)
Result: Water moves from the solution to inside the cell): Cell Swells and bursts open (cytolysis)!

16. Let’s take a closer look!

17. B C A What type of solution are these cells in? Hypertonic Isotonic
Hypotonic

18. Summary What is osmosis?
Is osmosis considered passive or active transport?
What are the 3 types of solutions involved in osmosis? 1. 2. 3.

19. How well did you do today?
What is Osmosis?
The movement of molecules.
The movement of molecules from an area of high concentration to low concentration.
The movement of water from a low concentration to a high concentration.
The movement of water from a high concentration to a low concentration.