1. 4/15/ :21 PM
7.3 Cell Transport
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2. 7.3 Cell Transport
Diffusion
Process by which particles lend to move from an area where they are more concentrated to an area where they are less concentrated.

3. Facilitated Diffusion
7.3 Cell Transport
Facilitated Diffusion
Process of diffusion in which molecules pass across the membrane through cell membrane channels.

4. 7.3 Cell Transport
Aquaporin
Water channel protein in a cell.

5. Osmosis Diffusion of water through a selectively permeable membrane.
7.3 Cell Transport
Osmosis
Diffusion of water through a selectively permeable membrane.

6. Isotonic When the concentration of two solutions is the same.
7.3 Cell Transport
Isotonic
When the concentration of two solutions is the same.

7. 7.3 Cell Transport
Hypertonic
When comparing two solutions , the solution with the greater concentration of solutes.

8. 7.3 Cell Transport
Hypotonic
When comparing two solutions , the solution with the lesser concentration of solutes.

9. 7.3 Cell Transport
Osmotic Pressure
Pressure that must be applied to prevent osmotic movement across the selectively permeable membrane.

10. Do Now
7.3 Cell Transport
_____When comparing two solutions , the solution with the lesser concentration of solutes.
Diffusion Hypotonic Osmosis Isotonic
_____ Process by which particles lend to move from an area where they are more concentrated to an area where they are less concentrated.
_____ When the concentration of two solutions is the same.
_____Diffusion of water through a selectively permeable membrane.

11. 7.3 Cell Transport
Just a thought
When thinking about how cells move materials in and out, it can be helpful to think of a cell as a nation. The boundaries of a nation are its borders, and nearly every country tries to regulate and control the goods the move across those borders.
Cells have their own borders, which separate the cell from its surroundings and also determine what comes in and what goes out.
How can a cell separate itself from its environment and still allow material to enter and leave?

12. Passive Transport What is passive transport?
7.3 Cell Transport
Passive Transport
What is passive transport?
The movement of materials across the cell membrane without using cellular energy is called passive transport.

13. Passive Transport Every living cell exists in a liquid environment.
7.3 Cell Transport
Passive Transport
Every living cell exists in a liquid environment.
One of the most important functions of the cell membrane is to keep the cell’s internal conditions relatively constant. It does this by regulating the movement of molecules from one side of the membrane to the other side.

14. 7.3 Cell Transport
Diffusion
The cytoplasm of a cell is a solution of many different substances dissolved in water.
In any solution, solute particles tend to move from an area where they are more concentrated to an area where they are less concentrated.
The process by which particles move from an area of high concentration to an area of lower concentration is known as diffusion.
Diffusion is the driving force behind the movement of many substances across the cell membrane.

15. 7.3 Cell Transport
Diffusion
Suppose a substance is present in unequal concentrations on either side of a cell membrane.

16. 7.3 Cell Transport
Diffusion
If the substance can cross the cell membrane, its particles will tend to move toward the area where it is less concentrated until it is evenly distributed.

17. 7.3 Cell Transport
Diffusion
At that point, the concentration of the substance on both sides of the cell membrane is the same, and equilibrium is reached.

18. 7.3 Cell Transport
Diffusion
At that point, the concentration of the substance on both sides of the cell membrane is the same, and equilibrium is reached.

19. 7.3 Cell Transport
Diffusion
Diffusion depends upon random particle movements. Substances diffuse across membranes without requiring the cell to use additional energy.
The movement of materials across the cell membrane without using cellular energy is called passive transport.