1. Solute vs. Solvent Solute: Solute: The substance being dissolved Solvent: Solvent: a liquid, gas, or solid capable of dissolving another substance (Water is the universal solvent)

2. Permeable vs. Impermeable Permeable – substances can pass through Permeable – substances can pass through Impermeable – substances cannot pass through Impermeable – substances cannot pass through Semipermeable? Semipermeable?

3. Semipermeable  A membrane that allows only certain materials to cross it  Materials pass through pores in the membrane

4. Diffusion Movement of molecules from an area of high concentration to an area of lower concentration Movement of molecules from an area of high concentration to an area of lower concentration Example: skunk, perfume, night after a dinner at taco bell! Example: skunk, perfume, night after a dinner at taco bell!

5. DEMO (Air Freshener) What molecules moved? What molecules moved? What direction did the molecules move? What direction did the molecules move? Location of molecules in the end? Location of molecules in the end?

6. DEMO (Food coloring) 1. What molecules moved? 2. What direction did the molecules move? 3. Location of molecules in the end? 4. How did heat effect the movement of the molecules? 5. How did cold effect the movement of the molecules?

7. Diffusion Draw a diagram of an example of diffusion we saw in class.

9. http://gened.emc.maricopa.edu/bio/bio181/ BIOBK/BioBooktransp.html http://gened.emc.maricopa.edu/bio/bio181/ BIOBK/BioBooktransp.html

10. Factors that affect Diffusion Temperature Temperature Size of Particles Size of Particles Concentration of Particles (number of molecules of a substance in a given volume ) Concentration of Particles (number of molecules of a substance in a given volume )

11. www.goldiesroom.org/video_archive.htm www.goldiesroom.org/video_archive.htm www.goldiesroom.org/video_archive.htm

12. Define osmosis  The diffusion of water across a selectively permeable membrane.  Semipermeable

13. Define osmosis  Water moves from a high concentration of water (less salt or sugar dissolved in it) to a low concentration of water (more salt or sugar dissolved in it). (more salt or sugar dissolved in it).  This means that water would cross a selectively permeable membrane from a dilute solution (less dissolved in it) to a concentrated solution (more dissolved in it).

14. Osmosis The diffusion of Water! The diffusion of Water! Which way is the water moving? Which way is the water moving? Which side is higher in water concentration? Which side is higher in water concentration? Less salt- more water More salt- less water AB →

15. http://www.usd.edu/~bgoodman/Osmos.htm Define osmosis

16. Types of Solutions Hypertonic Solution = higher concentration of water in the cell than outside the cell Hypertonic Solution = higher concentration of water in the cell than outside the cell Hypotonic Solution = higher concentration of water outside the cell than inside the cell Hypotonic Solution = higher concentration of water outside the cell than inside the cell Isotonic Solution = equal concentrations of water inside and outside the cell Isotonic Solution = equal concentrations of water inside and outside the cell

17. Osmosis Hypotonic Solutions: contain a low concentration of solute relative to another solution (e.g. the cell's cytoplasm). Hypotonic Solutions: contain a low concentration of solute relative to another solution (e.g. the cell's cytoplasm). When a cell is placed in a hypotonic solution, the water diffuses into the cell, causing the cell to swell and possibly explode. When a cell is placed in a hypotonic solution, the water diffuses into the cell, causing the cell to swell and possibly explode. http://www.tvdsb. on.ca/westmin/scie nce/sbi3a1/cells/os mosis.htm http://www.tvdsb. on.ca/westmin/scie nce/sbi3a1/cells/os mosis.htm http://www.tvdsb. on.ca/westmin/scie nce/sbi3a1/cells/os mosis.htm http://www.tvdsb. on.ca/westmin/scie nce/sbi3a1/cells/os mosis.htm

18. Osmosis Hypertonic Solutions: contain a high concentration of solute relative to another solution (e.g. the cell's cytoplasm). Hypertonic Solutions: contain a high concentration of solute relative to another solution (e.g. the cell's cytoplasm). When a cell is placed in a hypertonic solution, the water diffuses out of the cell, causing the cell to shrivel. When a cell is placed in a hypertonic solution, the water diffuses out of the cell, causing the cell to shrivel.

19. Osmosis Isotonic Solutions: contain the same concentration of solute as an another solution (e.g. the cell's cytoplasm). Isotonic Solutions: contain the same concentration of solute as an another solution (e.g. the cell's cytoplasm). When a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate. The fluid that surrounds the body cells is isotonic. When a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate. The fluid that surrounds the body cells is isotonic.

20. Osmosis In Blood Cells Hypotonic Hypertonic

21. Define 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. In the end pieces of cell membrane are left in the water. http://www.usd.edu/~bgoodman/Osmos.htm

22. Types of Solutions A. Hypotonic A. Hypotonic B. Hypertonic B. Hypertonic

23. Osmosis in Living Cells Cellulose in cell wall

24. Why are osmosis & diffusion important?  All living things have certain requirements they must satisfy in order to remain alive – maintain homeostasis  These include exchanging gases (usually CO 2 and O 2 ), taking in water, minerals, and food, and eliminating wastes.  These tasks happen at the cellular level.  Molecules move through the cell membrane by diffusion

25. Why are osmosis & diffusion important? All living things have certain requirements they must satisfy in order to remain alive. These include exchanging gases (usually CO 2 and O 2 ), taking in water, minerals, and food, and eliminating wastes. These tasks ultimately occur at the cellular level, and require that molecules move through the membrane that surrounds the cell. These tasks ultimately occur at the cellular level, and require that molecules move through the membrane that surrounds the cell.

26. Osmosis In Plant Cells

27. Review Osmosis & Diffusion Here: http://wappingersschools.org/WJH/t eachers/science/Jim_Site/asignment s/cells/diffusionetc/diffusion_osmosis.html http://wappingersschools.org/WJH/t eachers/science/Jim_Site/asignment s/cells/diffusionetc/diffusion_osmosis.html http://wappingersschools.org/WJH/t eachers/science/Jim_Site/asignment s/cells/diffusionetc/diffusion_osmosis.html http://wappingersschools.org/WJH/t eachers/science/Jim_Site/asignment s/cells/diffusionetc/diffusion_osmosis.html

28. A BC Classify each osmosis diagram as hypotonic, hypertonic, or isotonic solution.