1. maintaining homeostasis
Cell Transport
maintaining homeostasis
Chapter 5 in textbook

2. Passive Transport Does NOT require any ATP or energy
Happens automatically
Channels may be used in cell membrane

3. Passive Transport
This type of transport moves from an area of high concentration to low concentration

4. Diffusion Type of passive transport
When molecules move from an area of higher concentration to an area of lower concentration until equilibrium is met

5. What affects the rate of diffusion?
Concentration of the solution
Temperature of the solution
Pressure also speeds up particle motion

6. Concentration The amount of dissolved solute in a solution
Molecules will move to an area less concentrated
Molecules diffuse through the cell membrane of cells

7. Concentration gradient
The difference in concentration in a solution between a cell and its surroundings

8. Concentration Gradient
No gradient - even distribution
Concentration to the right
Concentration Gradient

9. Increase Rate of Diffusion
Temperature
Molecules move faster in higher temperatures
Pressure
Increasing pressure also increases rate of diffusion

10. Equilibrium
This occurs when there is no longer a concentration gradient
Molecules are evenly dispersed but still continue to move randomly

11. Cell Membrane Movement through membrane
Cell membrane is surrounded by water
Phospholipid bilayer

12. Cell Membrane Forms by itself in water Proteins imbedded Markers
Receptors
Channels

13. Diffusion in cells
Small molecules diffuse in and out of the cell to reach equilibrium on both side of the membrane

14. Osmosis Diffusion of water across a biological membrane
From an area of high concentration to low concentration of WATER
Comparing concentrations

15. Osmosis in Cells Cells are surrounded by water and filled with water.
Water can move freely through the membrane

16. Direction of Osmosis

17. Hypertonic Outside cell is more concentrated than cell
ex: 20% salt solution % salt solution
The solution with 20% salt is hypertonic compared to the 10% salt solution

18. Hypotonic Outside the cell is less concentrated than cell
ex: 10% salt solution % salt solution
The solution with 10% salt is hypotonic compared to the 20% salt solution

19. Isotonic Equal concentrations ex: 10% salt solution 10% salt solution
Equilibrium is reached

20. Osmotic Pressure Net movement of water into cells
Determined by solute concentration

21. Osmosis - hypertonic Higher concentration in solution
Ex: a cell in salt water
If molecules are too large to fit through cell membrane or protein channels
Water will diffuse OUT of the cell to reach equilibrium
Cell shrinks

22. Osmosis - hypotonic Lower concentration in solution
Ex: a cell in pure water
If molecules are too large to fit through cell membrane or protein channels
Water will diffuse INTO the cell to reach equilibrium
Cell swells - may burst!

23. Osmosis - Isotonic Equal concentration in solution
If molecules are too large to fit through cell membrane or protein channels
Water will diffuse IN AND OUT of the cell to maintain equilibrium

24. Osmosis in Plant Cells Turgor Pressure
Pressure on the walls of the plant cells due to vacuole filling
Increase in turgor pressure is increase in water to cell
Plasmolysis
When a cell shrinks due to lack of water

25. Red Onion Cells - Isotonic

26. Red Onion Cells - Hypertonic

27. Red Onion Cells - Hypotonic

28. Facilitated Diffusion
When the cell membrane has protein channels (carrier proteins) where materials are transported in or out of cell
NO energy needed for this process

29. Active Transport Against concentration gradient
From an area of low concentration to an area of high concentration
Requires cell energy (ATP) because you’re going AGAINST concentration gradient

30. 3 types of active transport
Protein channels embedded in cell membrane
Gated channels
Need energy to open
Protein changes shape when energy is used

31. Sodium/Potassium Pump
Step 1: 3 Na+ ions bind to carrier protein
Step 2: ATP binds to carrier protein and changes shape allowing Na+ to move out of the cell
Step 3: 2 K+ ions move into carrier protein
Step 4: ATP binds to carrier protein and changes shape allowing K+ to move into the cell

32. Movement in Vesicles Endocytosis - INTO the cell
Cell membrane is used to create a vesicle around particles
Phagocytosis
Particle ingestion
Pinocytosis
Liquid ingestion

33. Movement in Vesicles Exocytosis - OUT of the cell
Vesicles created in the cell fuse with cell membrane and release particles/liquids
Known as bulk transport