Post on 11-May-2015
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- 1.Diffusion & Osmosis
2. Define Diffusion 3. Define Diffusion
- The movement of molecules from a area in which they are highly concentrated to a area in which they are less concentrated.
4. Draw a diagram of an example of diffusion we saw in class. 5. Draw a diagram of an example of diffusion we saw in class. 6. Define osmosis 7. Define osmosis
- The diffusion ofwateracross a selectively permeablemembrane .
8. 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). 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).
9. Define osmosis 10. 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 byOSMOSIS . 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.
11. Define selectively permeable membrane
- A membrane that allows only certain materials to cross it
- Materials pass throughporesin the membrane
12. Two terms to study in this process 13.
- What is Hypertonic ?
- hypertonic is a solution which contains more solvent than solute (example: purified water--there's almost no solute dissolved in the solvent(water)
- What is Hypotonic?
- A solution with a lowersaltconcentration than in normal cells of the body and the blood. As opposed to anisotonic solutionor ahypertonic solution .
15. Why are osmosis & diffusion important?
- All living things have certain requirements they must satisfy in order to remain alive maintainhomeostasis
- 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 through the cell membrane by diffusion
16. Why are osmosis & diffusion important?
- All living things have certain requirements they must satisfy in order to remain alive. These include exchanging gases (usually CO2 and O2), 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.
17. Why are osmosis & diffusion important?
- 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.
- ANSWER THE FOLLOWING QUESTIONS
- 1. What is osmosis?
- 2. What is passive transport?
- 3. What happens in exocytosis?
- 4. What is endocytosis, what happens?
- 5. Make an illustration explaining each one of them.
- 6. What happens during osmosis?
- 7. Why is diffusion important?
- 8. Why is osmosis important?
- THANK YOU