1. Bell Ringer: 10/25/17
Objective: Explain the mechanisms of passive transport.
Questions:
Complete bottom ten questions of yesterday’s worksheet.

2. Channels allowing certain molecules through that are too large to go straight through the cell membrane.

3. Passive Transport Does not use energy (ATP)
Solutes move through a channel on the inside of a protein
Net movement is down the concentration gradient
(high → low)
What does solute mean? (thing be dissolved)

4. Types of Passive Transport
Diffusion
Osmosis
Facilitated Diffusion
High conc. → low conc. with the help of a protein channel

5. Passive Transport of Glucose
PROTEIN
Solute (glucose)
high
low

6. A drop of dye enters a bowl of water. What happens? Why?
What factors impact the reaction?

7. Cell Transport & Diffusion
Movement from high concentration to low concentration
Substances diffuse independently of each other
Other key terms:
Brownian Motion
Constant random motion of molecules
Dynamic Equilibrium
Continuing movement of molecules with NO overall/net change in diffusion

8. Factors Affecting Diffusion Rate
Steepness of concentration gradient
Steeper gradient, faster diffusion
Molecular size
Smaller molecules, faster diffusion
Temperature
Higher temperature, faster diffusion

9. Diffusion Experiment

10. Osmosis Net movement of water from high → low
Between two regions separated by a selectively permeable membrane
Blue Dot = Solute
Red dot = H20

11. Water Concentration Gradient
Water concentration gradient means the number of water molecules on one side of the membrane is different than the number of molecules on the other side
of the membrane.

12. semipermeable membrane between two compartments
water
molecule
protein
molecule

13. Solute concentrations effect osmosis: The membrane side with the most solute particles has the lower water concentration.

14. Differences in Concentration
When two fluids on opposing sides of a membrane differ in solute concentration…
Hypotonic solution
More water
Less solutes
Hypertonic solution
Less water
More solutes
Isotonic solution
Same water
Same solute

15. 2% sucrose
solution
10% sucrose
solution
2% sucrose solution
distilled water
Hypotonic
Conditions
Hypertonic
Conditions
Isotonic
Conditions

16. What happens when a cell cannot contain an excessive inflow of water?
Cytolysis-> the process that occurs when a cell cannot contain an excessive inflow of water. (occurs in animal cells and certain bacteria)
What happens when a cell cannot contain an excessive inflow of water?

17. Osmotic Burst of Red Blood Cells

18. Day Two: Be VERY careful holding your egg
Egg Experiment
Day Two: Be VERY careful holding your egg

19. OSMOSIS WORKSHEET
On weebly under Cell Structure & Transport in Class work  Answer on a lined sheet of paper

20. Closure Define diffusion. What are the 3 types?
Draw a picture illustrating a hypotonic solution.
What is the cell membrane composed of?