Transcript 3.2 Osmosis
Osmosis September 2, 2009 Objective: SWBAT predict water movement in hyper/hypotonic solutions. Catalyst: Define selectively permeable. Give an example of diffusion in real life. Agenda Catalyst Review Diffusion Review Osmosis Hyper, Hypo, Iso Predict Movement Exit Question Catalyst Review Selectively permeable means something that only allows specific things through. Diffusion— volunteers? Diffusion Review Movement of solutes from high to low until… HIGH LOW Diffusion Review …concentration is equal (EQUILIBRIUM) EQUAL = EQUAL By the end of today… You should be able to tell me why you shouldn’t drink salt water if you are stranded in the middle of the ocean. You should be able to explain some of the symptoms of diabetes. It all relates to… Osmosis! Key Point #1: Osmosis is the diffusion of water to equalize concentrations. Blue=water, Green=solute Blue=water, Green=solute Which way will it move? Think to yourself- which side has the higher concentration of particles? Which way do the particles want to move? In osmosis- WATER moves the OPPOSITE direction as diffusion to equalize concentrations. OSMOSIS The BLUE dots are moving in osmosis Prefixes-write these in your notes Hypo-less than Hyper-more than Iso-same as Make a table in your notes Isotonic Hypotonic Hypertonic Equal concentrations of impermeable solutes inside and outside. No net movement of water. Less concentration of impermeable solutes outside the cell. Water moves into the cell. Cell may burst which is called lysis. Higher concentration of impermeable solutes outside the cell. Water moves out of the cell. Cell shrinks. Group thought time- do this for each situation. Draw a picture of each of these situations. Which way would solutes move if they could? In osmosis, solutes are impermeable. Instead, water will move the OPPOSITE way. Example: Hypertonic Solutes would want to move inside, but they can’t. So, water will move OUTSIDE. See if you agree If you got these correct in your group- you do not need to take notes. Make sure to correct your stuff in case it was incorrect. Isotonic Hypotonic Solutes and water would stay where they are since concentrations are equal. Solutes would want to move outside, but they can’t. So, water will move INSIDE. Isotonic Solution Outside Cell Inside Cell Hypotonic Solution Inside Cell Outside Cell Hypotonic Solution Inside Cell Outside Cell Water Water Water Hypotonic Solution Inside Cell Water Outside Cell Water Water Hypertonic Solution Inside Cell Outside Cell Hypertonic Solution Inside Cell Outside Cell Water Water Water Hypertonic Solution Water Inside Cell Water Outside Cell Water Red blood cells in action http://www.coolschool.ca/lor/BI12/unit4/U04L06/ rbc.html Hypo, hyper or isotonic? More solute inside the cell than outside 1) Write either hyper, hypo, or isotonic 2) Write which way the water is flowing (into or out of the cell) Hypo, hyper or isotonic? Equal solute inside the cell and outside the cell 1) Write either hyper, hypo, or isotonic 2) Write which way the water is flowing (into or out of the cell) Hypo, hyper or isotonic? 40% sugar inside the cell and 10% sugar outside the cell 2) Where is the water flowing? 1) Write either hyper, hypo, or isotonic 2) Write which way the water is flowing (into or out of the cell) Hypo, hyper or isotonic? 10% sugar inside the cell and 90% sugar outside the cell 2) Where is the water flowing? 1) Write either hyper, hypo, or isotonic 2) Write which way the water is flowing (into or out of the cell) Define What is lysis? What kind of solution (hypo, iso, or hyper) does it occur in? Worksheet (IP) This is your worksheet- finish it here and anything you do not finish is homework for tonight. Exit Question Which one of these situations (left, middle, right) represents a cell in a hypertonic solution? Would water go into or out of the cell?