1. Getting Into and Out of Cells
Cell Transport

2. Cell Membrane
Regulates what enters and leaves the cell and provides protection, support and shape
Made out of a phospholipid bilayer
Gives it flexibility
Also find protein embedded in the layer
Which act as tunnels or pumps that help to move materials.
Some have carbohydrates attached
act like chemical ID cards
Allows individual cells to identify one another

3. Fluid Mosaic Model
Fluid Mosaic Model

4. What Is a Phospholipid?
Each phospholipid is composed chemically of 2 fatty acids, a glycerol and a phosphate.
Hydrophobic Tails are repelled by water. “water fearing”
Hydrophilic Heads are attracted to water. “ water loving”
Heads of phospholipid are hydrophilic.
Tails of phospholipid are hydrophobic

5. What Is a Phospholipid? Hydrophilic Hydrophobic
Heads of phospholipid are hydrophilic.
Tails of phospholipid are hydrophobic
Hydrophobic

6. Additional Material found in the Cell Membrane (add to back of keystone card!)
Glycoproteins - different surface markers or antigens, which are used as signals to distinguish different cells.
Integral Proteins - are proteins that go all the way through the bilayer. Can be referred to as channel proteins and help move large molecules across the membrane.
Peripheral Proteins - are found only one side of the membrane
Cholesterol is a steroid that help strengthen the membrane and make it less sensitive to lysis.

7. Include the title of the Card; Draw a diagram of a Phospholipid, glue the colored diagram of the Cell Membrane. On the BACK define The terms including the letters from the front
(you can not define the first and last words!)
FLUID MOSAIC MODEL

8. Types of Cell Transport
Passive Transport
- no cellular energy required to occur
- goes with the concentration gradient
- diffusion
- facilitated diffusion
- osmosis
Active Transport
- requires cellular energy to occur
- goes against the concentration gradient
- Endocytosis/Exocytosis
- Sodium Potassium Pump

9. Concentration Gradient
The concentration gradient is the distribution of particles across space from high to low concentration

10. Passive Transport
In passive transport, molecules move with the concentration gradient
- move from high concentration to low concentration

11. Diffusion Primary means of cell transport
- molecules move from high to low concentration
- movement continues with the gradient until the molecules are evenly distributed and equilibrium is achieved

12. Include the title of the Card; Draw a diagram of a Phospholipid, glue the colored diagram of the Cell Membrane. On the BACK define The terms including the letters from the front
(you can not define the first and last words!)
FLUID MOSAIC MODEL

13. Facilitated Diffusion
Particles move with the concentration gradient
using a transport protein in the membrane.
- ions, sugar and amino acids all move into and
out of cells by facilitated diffusion

14. Osmosis The diffusion of water across a selectively permeable membrane
- water moves down the concentration gradient.
- water moves toward higher conc. of dissolved
material - solute

15. Three Osmotic environments
Hypotonic
Hypertonic
Isotonic

16. Hypotonic
If concentrations of dissolved solutes are less outside the cell than inside, then water will move into the cell.
Cells without walls will swell and may burst (lyse) if excess water is not removed from the cell.
Cells with walls often benefit from the turgor pressure that develops in hypotonic environments.

17. Hypotonic Environment
Animal Cell Plant Cell
Before
Place in Distilled Water
Water moves In
burst turgid

18. Hypertonic
If concentrations of dissolved solutes are greater outside the cell, then water inside the cell will flow outwards to attain equilibrium.
This causes the cell to shrink.
As cells lose water, they lose the ability to function or divide.

19. Hypertonic Environment
Animal Cell Plant Cell
Before
Place in Salt Water
Water Moves Out
Shrivel up

20. Isotonic
Concentration of solute inside and outside of the cell is equal.
Water moves in and out of the cell at equal rate.
No change in the cell.

21. Isotonic Environment Animal Before Plant Water Moves In and Out
at an Equal rate
No Change No Change

22. Plasmolysis—loss of water due to osmosis
Normal Plant Cells in Hypotonic Solutions
In Plant Cell membrane pulls away from the cell wall.

23. Cytolysis Cytolysis: Cell Swelling from uptake of water
This usually takes place when cells are placed in a hypotonic solution such as distilled water.
Normal/Isotonic
Plasmolyzed/Hypertonic
Cytolysis

24. Osmotic Environments
Define on the back of the card: HYPOTONIC, HYPERTONIC AND ISOTONIC

25. Active Transport
Requires energy (ATP) because it goes against the gradient.
Small molecules or ions across the membrane is carried out by transport protein and “pumps”.
Large molecules can cross the membrane by endocytosis and exocytosis.

26. Types of active transport
Endocytosis (into cell) and exocytosis (out of cell)
Pinocytosis – movement of liquid into and out of the cell.
Phagocytosis – movement of solute particles into and out of the cell.
Gated ion channels
Sodium/potassium pumps

27. Endocytosis and Exocytosis
Vesicle form in the cell
Moves and attaches to the membrane
Releases materials outside of the cell.
Endocytosis
Membrane forms into vesicle.
Detaches from membrane
Pulls materials into the cell.

28. Sodium Potassium Pump
The protein “pumps” the sodium ion (Na+) out of the cell and potassium (K+) into the cell.
ATP provides the energy that keep the pumps working.
Is needed for the electrical impulse nerves

29. Gated ion channels Messenger attaches to receptor protein
Reaction occurs which supplies energy to the gated protein.
Channel opens to allow ions to enter.

30. Challenge Question
Explain why a salt water fish cannot survive in freshwater.
Use the terms hypotonic, hypertonic and isotonic to explain.