Diffusion and Osmosis

1. Diffusion and Osmosis

2. TSWBAT identify the process of osmosis and diffusion via the gummi bear lab-analyze diffusion through a sand baggie and apply the concepts of hypotonic, hypertonic, and isotonic to the activity • On a blank sheet of paper • Write the equation for cellular respiration. • Where does cellular respiration occur in the cell? • List the organelles that help to make proteins • What is the difference between the rough and the smooth endoplasmic reticulum?

3. 1 4 2 3 Diffusion • Solvent – what dissolve something • Solute – what is being dissolved • Solute molecules moving from an area of high concentration to an area of low concentration • Random motion drives diffusion • Movement is based on kinetic energy (speed), charge, and mass of molecules • Equilibrium is reached when there is an even distribution of solute molecules • http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html (water)

4. Osmosis • Diffusion of water through a semi-permeable membrane • Semi-permeable: permeable to solvents (WATER), but not to large molecules • High [water] to low [water] • Dissolved molecules (i.e. glucose, starch) are called solutes • REMEMBER: Water = solvent Glucose, Starch = solutes http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html

5. Effect of Water on Cells • Hypertonic Environment • High [solute], low [water] • The cell will shrink • Plasmolysis – cell death Hypotonic Environment • High [water], low [solute] • Plants – turgor pressure – plant like this!! • Animals – cytolysis – cell bursting • Isotonic Environment • [water] = [solute] Hypertonic Hypotonic Isotonic Part 3 pg. 85

6. Cellulose in cell wall Osmosis in Living Cells

7. Isotonic Predictions? Hypertonic Hypotonic Osmosis in Red Blood Cells • 0.9% saline • 10% NaCl • Distilled water Plasmolysis

8. Hypertonic Predictions? Hypotonic Osmosis in Plant Cells Plasmolysis • . • 10% NaCl • Distilled water

9. Animations Dialysis Bag Experiment • http://ccollege.hccs.cc.tx.us/instru/Biology/AllStudyPages/Diffusion_Osmosis/Baggif.swf Elodea Cell • http://ccollege.hccs.cc.tx.us/instru/Biology/AllStudyPages/Diffusion_Osmosis/Elodeagif.swf Osmosis • http://ull.chemistry.uakron.edu/genobc/animations/osmosis.mov

10. Transportation of Molecules • Passive Transport • Movement of molecules across a semi-permeable membrane • no energy required • Active Transport • Movement of molecules across a semi-permeable membrane against a concentration gradient with a protein • ENERGY – ATP • Facilitated Diffusion • Movement of molecules across a semi-permeable membrane with a protein • no energy required

11. Effect of Water on RBC