Osmosis and Tonicity PowerPoint PDF
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This presentation covers cell structure and function and then delves into osmosis and tonicity (hypertonic, hypotonic, isotonic) in plant and animal cells, including examples, diagrams, and practice questions.
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Cell Structure and Function Notes #2 Osmosis and Tonicity (Hypertonic, Hypotonic, Isotonic) Chapter 7 in Methods of Transpor...
Cell Structure and Function Notes #2 Osmosis and Tonicity (Hypertonic, Hypotonic, Isotonic) Chapter 7 in Methods of Transport across Cell Membranes Osmosis the diffusion of __________ water across the cell membrane. Is ATP energy required for osmosis? NO Aquaporin transmembrane _______________: protein that enables water to passively diffuse across the plasma membrane. *why can’t water move across the cell membrane using simple diffusion? It is a polar molecule and most of the phospholipid bilayer is composed of nonpolar fatty acid “tails.” Osmosis continued…. Water Starch Starch is a polysaccharide that is TOO LARGE to cross the plasma membrane (*even with a transmembrane protein). solute (e.g. salt, starch, glucose, or some other molecule dissolved in a solution) When a __________ is too large to cross the cell membrane, what happens? Water will move TOWARD the side with a HIGHER solute concentration via osmosis MORE ON How do we OSMOSIS!!! determine which way water will move via osmosis??? To figure it out, we must understand tonicity! Tonicity is a Relative Term Hypotonic Solution - one solution has a lower concentration of solute than another. Hypertonic Solution - one solution has a higher concentration of solute than another. Isotonic Solution - both solutions have same concentrations of solute. 3.) Osmosis continued…. Hypotoni c Hypotonic: describes a solution that has a _____________ solute LOWER concentration than another solution. Answer the following questions based on the solution to the left: hypotonic The solution surrounding the cell is _______________ compared to the solution within the cell. hypertonic The solution within the cell is _______________ compared to the solution surrounding the cell. In which direction will water move? *water will move toward Into the cell where there is more solute What might happen to the cell? Swell and burst open (cytolysis) in animal cells; turgid in plant cell 3.) Osmosis continued…. Hypertoni c Hypertonic: describes a solution that has a _____________ solute HIGHER concentration than another solution. Answer the following questions based on the solution to the left: hypertonic The solution surrounding the cell is ______________ compared to the solution within the cell. hypotonic The solution within the cell is _______________ compared to the solution surrounding the cell. In which direction will water move? *water will move toward Out of the cell where there is more solute What might happen to the cell? Shrink/shrivel up (plasmolysis in plant cells) Isotonic 3.) Osmosis continued…. Isotonic: describes a solution that has the _____________ SAME solute concentration than another solution. Answer the following questions based on the solution to the left: isotonic The solution surrounding the cell is ______________ compared to the solution within the cell. isotonic The solution within the cell is _______________ compared to the solution surrounding the cell. In which direction will water move? Into and out of the cell at equal rates (dynamic equilibrium) What might happen to the cell? Stay the same size MORE ON OSMOSIS!!! Animal cells and plant cells behave differently when placed in hypotonic and hypertonic solutions. This is because plants have a strong outer cell wall while animal cells do not. Draw the cell membrane of an animal cell in the space below. Draw the cell membrane AND cell wall of a plant cell in the space below. Animal Cell Plant Cell Cell Wall *the cell wall of an Cell plant cell is located Membrane Cell outer the cell _________ Membrane membrane (it is the outmost part of the cell). It is made of cellulose and ____________ is strong and rigid. Animal Cell vs Plant Cell in a HYPOTONIC Environment Red Blood Cell Placed in Plant cell placed in a a HYPOtonic solution HYPOtonic solution Water will enter plant cell. Plant cell will Water will enter cell; too much water could turgid (“swollen”) but the become __________ cause cell to burst (________) cytolysis cell will NOT burst. Animal Cell vs Plant Cell in a HYPERTONIC Environment Red Blood Cell placed in a HYPERtonic solution Plant Cell placed in a HYPERtonic solution In plants, shriveling of the cell membrane is plasmolysis called ________________________. The In animal cell, the cell will shrivel/shrink. cell membrane will pull away from the cell wall and shrink! Cells surrounded by HYPERtonic solutions Surround plant cells with salt Shrinks In animal cell, the cell will shrink. In plants, shriveling of the cell membrane is called PLASMOLYSIS. The cell membrane will pull away from the cell wall and shrink! ps://www.youtube.com/watch?v=Iv7eGCPVaAk d Onion Osmosis – Plasmolysis – Microscope Video (2:54 min) 3.) Osmosis continued…. Nemo is a saltwater fish and has cells with a relatively high solute concentration. Make a drawing showing what will happen to Nemo if he is place in fresh water which has a LOWWhich salt/solute concentration. way would the water Into his cells move???? Water will enter his cells and What will happen to Nemo??? they will burst (cytolysis)…. Nemo will die Solution is hypotonic compared to the cells Which way will water move (in or out of Into the the Whatcell)? will happen to the red blood cell cellIt will (shrink or burst)? burst Pure/DI Solute in red water (no blood cell salt) in IV bag Beef jerky lasts a lot longer than normal meats before it goes bad. Why do you think drying out the beef jerky with a lot of SALT allows it to stay fresher longer? Water goes out of bacteria cell, causing it to die Bacteria Beef Jerky (not a lot of (a lot of Practice Questions 1. In osmosis, water always moves toward the ______ solution. In other words, water moves toward the solution with the _______ solute concentration. A.) isotonic... greater B.) hypertonic... greater C.) hypertonic... lesser D.) hypotonic... greater E.) hypotonic... lesser 2. The concentration of calcium in a cell is 0.3%. The concentration of calcium in the surrounding fluid is 0.1%. How could the cell obtain more calcium? A.) passive transport B.) diffusion C.) active transport D.) osmosis E.) any of the prior methods could be used Practice Questions 3. Movement of which of the following would require ATP hydrolysis? 4. What type of transport is oxygen able to perform? Why?