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On right hand side of a clean page write:. 1
On right hand side of a clean page write: Update TOC: Movement Across Cell Membrane 2. Write Critical question, and 3. Turn to your Venn Diagrams What is the difference between simple diffusion, facilitated diffusion, and active transport?
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Cell (plasma) membrane
What do cells move in and out (phospholid layers and protein channel)? IN food - sugars - proteins - fats salts O2 H2O OUT waste - ammonia - salts - CO2 - H2O products - proteins cell needs materials in & products or waste out
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2 Ways of Crossing cell membrane
Structure of Cell: Phospholipid Bilayer 2 Ways of Crossing cell membrane 1. If the molecules are small enough Small molecules can easily pass through spaces of the cell membrane O2 CO2 H2O 2. If the are soluble (hydrophobic, non-polar, etc.) inside cell outside cell ions Hydrophilic molecules & Proteins cannot move through the membrane on its own. salt waste water but… what about other stuff? lipid sugar aa
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Protein Channels Structure of Cell: Are“doors” through the membrane
protein channels allow insoluble molecules in & out Channels are specific to the molecules they let in & out salt, sugar, amino acid, certain waste, etc. inside cell aa sugar salt outside cell waste
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How do molecules just move through a membrane?
Molecules like to spread out!! They will always go from an area of A LOT of molecules to a little amount of molecules? HIGH ? 1 LOW ?
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Types of Transport (Movement) Across Cell Membranes
The Plasma Membrane 5/29/2018 Types of Transport (Movement) Across Cell Membranes Passive Transport 2. Active Transport - Simple Diffusion (Ex: Osmosis- water) - Facilitated Diffusion copyright cmassengale G. Podgorski, Biol. 1010
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Can cross over a membrane
Simple Diffusion: Passive Diffusion: movement of molecules from an area of HIGH to LOW concentration across a semi permeable membrane no energy needed No protein channel needed diffusion of water diffusion Can cross over a membrane osmosis
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Simple Diffusion: Practice
Molecules Move from HIGH to LOW fat fat fat Which way will fat move? inside cell fat fat fat LOW HIGH fat outside cell fat fat fat fat fat fat fat
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Facilitated Diffusion
Facilitative Transport: Passive Molecules Move from HIGH to LOW through a channel sugar sugar sugar sugar inside cell sugar sugar LOW Which way will sugar move? HIGH outside cell sugar sugar sugar sugar sugar sugar sugar
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Simple vs. facilitated diffusion
Both Passive!! This means they both do or don’t require energy? simple diffusion facilitated diffusion lipid inside cell outside cell inside cell outside cell NA+ protein channel lipid NA+ lipid NA+ lipid lipid NA+ NA+ NA+
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facilitated diffusion
WAIT!!! Brainstorm with your groups the answer to the following question. If simple diffusion & facilitated transport don’t require energy, why do organisms get tired? Is there another type of transport that doesn’t occur naturally, and therefore makes us use energy? simple diffusion facilitated diffusion inside cell outside cell lipid inside cell outside cell NA+ protein channel lipid NA+ lipid NA+ lipid lipid NA+ NA+ NA+
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Active transport Cells may need molecules to move against concentration gradient from LOW to HIGH using energy protein pump requires energy ATP Plants have nitrate & phosphate pumps in their roots. Why? Nitrate for amino acids Phosphate for DNA & membranes Not coincidentally these are the main constituents of fertilizer. ATP
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Exit Ticket Draw & Label the Transport Summary Diagram
simple diffusion facilitated diffusion WORD BANK Active Transport Passive Transport Simple Diffusion Facilitated Diffusion Requires Energy ATP active transport Requires Energy Requires Energy
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Critical Question What is the difference between simple diffusion, facilitated diffusion, and active transport?
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Osmosis: Movement of Water Across Cell Membrane
Warm Up: Label the diagram below with its correct vocabulary word – Solution 4. doing dissolving 2. Solvent 5. being dissolved 3. Solute
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Is Osmosis passive or active?
Is it facilitated or simple diffusion? Brainstorm!! Which direction do you think the water will move in diagram 1? What do you think will happen to the yellow circle’s size? Water’s properties are unique, so we talk about water separately! Osmosis diffusion of water from HIGH concentration of H20 (low solute) to LOW concentration of H20 (high solute) Label the yellow circles 1 & 2 - high concentration low solute or low concentration high solute
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Types of Solutions Hypertonic Hypotonic
When water leaves the cell because the Solution has a: High Concentration solute Less water When water enters the cell because the Solution has a: Low Concentration solute More water
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Equal amount of molecules leaving and entering the cell
Keeping water balance Cell survival depends on balancing water uptake & water loss Equal amount of molecules leaving and entering the cell Isotonic Hypotonic Hypertonic
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Keeping right amount of water in cell
1 Keeping right amount of water in cell Hypotonic a cell in fresh water high concentration (more) of water around cell cell gains water example: Paramecium problem: cells gain water, swell & can burst water continually enters Paramecium cell solution: contractile vacuole pumps water out of cell KABOOM! freshwater No problem, here
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Keeping right amount of water in cell
2 Keeping right amount of water in cell Hypertonic a cell in salt water Less / low concentration of water around cell cell loses water example: shellfish problem: cell loses water in plants: plasmolysis in animals: shrinking cell solution: take up water I’m shrinking, I’m shrinking! saltwater I will survive!
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Keeping right amount of water in cell
3 Keeping right amount of water in cell Isotonic no difference in concentration of water between cell & environment cell in equilibrium example: blood problem: none water flows across membrane equally, in both directions volume of cell doesn’t change That’s better! balanced I could be better…
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Appling A young woman decides to go for a hike in Yellowstone National Park on a summer day. She brings: a water bottle, protein bar, hat, some sunscreen and bear repellant. Before her hike, she has a very good breakfast including eggs, oatmeal, fruit, and orange juice. At the beginning the 9 am hike, the day is cool and she’s wearing shorts, a t-shirt, and a light jacket. By noon, she has hiked 5 miles, it is 95 degrees, and very sunny. Describe what cellular processes are occurring to the woman during the day. What occurs inside her body after eating breakfast? What occurs inside her body as she starts her hike? What occurs inside her body as the day warms, and how might she respond to this? At noon, what may be occurring at a cellular and body level, and why? Within your group, answer the questions, brainstorm, and create a list of what may be occurring at both the cellular & body level for this woman. Create your list in your Engage Student Handout. Once your group has completed your list, raise your hand.
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