1. Beginning Vocab. Words 
Solute = substance being dissolved
Solvent = substance that dissolves the solute (usually water)
Solution = solute + solvent

3. Movement of Materials Into & Out of the Cell
Active & Passive Transport

4. Define: Selectively Permeable Membrane
A membrane that allows only certain materials to cross it
Materials pass through pores in the membrane

5. Define: Selectively Permeable Membrane (continued)
This membrane is a complex structure that is responsible for:
separating the contents of the cell from its surroundings, for
controlling the movement of materials into and out of the cell,
and for interacting with the environment surrounding the cell.

6. Define: Selectively Permeable Membrane (continued)
All living things have certain requirements they must satisfy in order to remain alive – maintain homeostasis
These include exchanging gases (usually CO2 and O2), taking in water, minerals, and food, and eliminating wastes.
These tasks happen at the cellular level.
Molecules move easily through the cell membrane by diffusion
Not all substances can easily diffuse through the membrane…

7. Types of Cellular Transport
Passive Transport
cell doesn’t use energy
Diffusion
Facilitated Diffusion
Osmosis
Active Transport
cell does use energy
Protein Pumps
Endocytosis
Exocytosis

8. This is gonna be hard work!!
Types of Cellular Transport
___________ transport
high
low
Weeee!!!
high
low
This is gonna be hard work!!
Passive = high to low
Active = low to high
___________ transport

9. PASSIVE TRANSPORT

10. Passive Transport Movement of materials into and out of a cell
No energy required
Moves from [high] to [low]
(Concentration gradient = difference between region of high concentration and region of low concentration
(3) types:
Diffusion, Facilitated diffusion, Osmosis

11. P.T.  Diffusion (High to Low)
Diffusion: random movement of particles from an area of high concentration to an area of low concentration.
(High to Low)
Diffusion continues until all molecules are evenly spaced (equilibrium is reached)-Note: molecules will still move around but stay spread out.
Occurs when small molecules pass through the lipid bilayer of a cell membrane

12. Example of Diffusion

13. Food Coloring example

14. P.T.  Facilitated DiffusionB
P.T.  Facilitated Diffusion
2. Facilitated diffusion: diffusion of specific particles through transport proteins found in the membrane
Transport Proteins are specific – they “select” only certain molecules to cross the membrane
Transports larger or charged molecules
Facilitated diffusion (Channel Protein)
Diffusion (Lipid Bilayer)
Follows the same rules as regular, simple diffusion (high to low concentration and no energy input) BUT, uses protein carrier molecules to allow substances to move through
Fac. Diffusion depends on carrier proteins embedded in the membrane to allow specific substance to pass through that might not be able to diffusion through the cell/plasma membrane
Carrier Protein

15. P.T.  Facilitated Diffusion
Cellular Transport From a:
Glucose
molecules
High Concentration
Cell Membrane
Low Concentration
Protein
channel
Transport Protein
Through a 
Channel Proteins animations
Go to Section:

16. Osmosis animation
P.T.  Osmosis
3.Osmosis: diffusion of water through a selectively permeable membrane
Water moves from [high] of water (less solute dissolved in it) to [low] of water (more solute dissolved in it)
Water crosses from dilute solution (less dissolved)to concentrated solution (more dissolved)
Water moves freely through pores.
Solute (green) is too large to move across.

17. Effects of Osmosis on Life
Water is so small and there is so much of it the cell can’t control it’s movement through the cell membrane.

18.  Lower concentration of solute (sugar) Higher of sugar
Same concentration
Selectively
permeable mem-
brane: sugar mole-
cules cannot pass
through pores, but
water molecules can
More free water
molecules (higher
concentration)
Water molecules
cluster around
sugar molecules
Fewer free water
molecules (lower
Water moves from an area of higher
free water concentration to an area
of lower free water concentration 
Osmosis

19. Osmosis
In this picture a red blood cell is put in a glass of distilled water (all water with no salt or sugar in it). 
Because there is a higher concentration of water outside the cell, water enters the cell by OSMOSIS. 
In this case too much water enters and the cell swells to the point of bursting open. 

20. Solutions
Part 2

21. Solutions Any homogeneous mixture
Homogeneous mixture-mixture that is evenly distributed, but can be separated
Example: salt water, to separate- evaporate water and then salt is left over

22. Talking about solutions = Talking about “Tonicity”
The amount of solutes in a solution
3 types: hypertonic, hypotonic, isotonic

23. Hypotonic Solution
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)!

24. Turgor Pressure
The pressure in a plant cell due to osmosis (diffusion of H2O into the cell).

25. Turgor Pressure

26. 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

27. Cytolosis
A red blood cell is put in a glass of distilled water.  Water enters the cell. 
In this case too much water enters and the cell swells to the point of bursting open (cytolosis). 

28. Plasmolysis The shrinking of the cytoplasm (cell) due to loss of H2O.
Normal Plasmolysis

29. Isotonic Solution
Isotonic: The concentration of solutes in the solution is equal to the concentration of solutes inside the cell.
*same [dissolved substances] in solution as in the cell
Result: Water moves equally in both directions and the cell remains same size! (Dynamic Equilibrium)

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

33. ACTIVE TRANSPORT

34. Movement of materials against a concentration gradient
Active Transport
Movement of materials against a concentration gradient
Moves from [low] to [high]
Bicycle and hill example

35. Active Transport, type 1
Transport or Surface Proteins
Substance moves across a membrane by binding to transport protein
(similar to facilitated diffusion except moving from low to high conc.)
Needs energy!

36. A.T.  Ex. of transport proteins
Sodium Potassium Pumps (Active Transport using proteins)
A.T.  Ex. of transport proteins
Protein Pumps -transport proteins that require energy to do work
Example: Sodium / Potassium Pumps are important in nerve responses.
Ex of transport
Protein changes shape to move molecules: this requires energy!

37. Endocytosis and Exocytosis
Active Transport, type 2
Material enters or exits a cell by becoming enclosed in a membrane vesicle
Endocytosis and Exocytosis

38. Examples of Membrane Bound Active Transport
Endocytosis: transporting material into cell by vesicle
Exocytosis: transporting material out of cell by vesicle
Requires energ

39. Types of Active Transport
2. Endocytosis: taking bulky material into a cell
Uses energy
Cell membrane in-folds around food particle
“cell eating”
forms food vacuole & digests food
This is how white blood cells eat bacteria!

40. Pinocytosis: small liquids are taken into cell by vesicle
Endocytosis
Pinocytosis: small liquids are taken into cell by vesicle
Phagocytosis: solid particles ingested into cell by vesicles

41. Figure 7.20 Exploring Endocytosis in Animal Cells
PHAGOCYTOSIS
PINOCYTOSIS

42. Types of Active Transport
3. Exocytosis: Forces material out of cell in bulk
membrane surrounding the material fuses with cell membrane
Cell changes shape – requires energy
EX: Hormones or wastes released from cell
Endocytosis & Exocytosis animations

43. Exocytosis

44. http://programs. northlandcollege