diffusion & osmosis
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DESCRIPTIONDiffusion & Osmosis. Schema Activator. Evaluate the following claims: 9 out of 10 people surveyed say that the bag lunches at GPA are among the best they’ve ever had 100% of people surveyed say that cell phones and music players should not be allowed in schools - PowerPoint PPT Presentation
Diffusion & Osmosis
Schema ActivatorEvaluate the following claims:
9 out of 10 people surveyed say that the bag lunches at GPA are among the best theyve ever had
100% of people surveyed say that cell phones and music players should not be allowed in schools
What questions come to mind when you read these statements?
Movement of MaterialsWe have looked at cells and the structures that help make and transport materials throughout the cellHow do the materials enter and leave the cell?Cell membrane- selectively permeablewrite what you think this means in your science notebooks
Define selectively permeable membraneA membrane that allows only certain materials to cross it Materials pass through pores in the membrane
Structure of Cell MembraneLipid bilayerHydrophilic headsHydrophobic tailsCarrier proteins
The cell membrane has a unique structure that controls how things enter and leave the cell, referred to as the fluid mosaic model
How Materials MoveMaterials move through the cell membrane through a process called Diffusion
Write down what you think diffusion is in your science notebook.
Define DiffusionThe movement of molecules from a area in which they are highly concentrated to a area in which they are less concentrated.
Draw a diagram of an example of diffusion we saw in class.
See an animation of diffusion here:http://lewis.eeb.uconn.edu/lewishome/applets/Diffusion/diffusion.html
Define osmosisThe diffusion of water across a selectively permeable membrane.
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).
http://www.usd.edu/~bgoodman/Osmos.htm Define osmosis
Define osmosisIn 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 by OSMOSIS. 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. http://www.usd.edu/~bgoodman/Osmos.htm
See an animation of osmosis here:http://lewis.eeb.uconn.edu/lewishome/applets/Osmosis/osmosis.html
For more information on diffusion & osmosis, click here:http://edtech.clas.pdx.edu/osmosis_tutorial/default.html
Types of Passive TransportDiffusionOsmosisFacilitated DiffusionCarrier ProteinsIon channelsSome always openSome gated
Why are osmosis & diffusion important?All living things have certain requirements they must satisfy in order to remain alive maintain homeostasisThese 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
Active TransportIf passive transport is the movement of materials from an area of greater to lesser concentration, what do you suppose active transport is? Write your answer in your science notebook
Types of Active Transport:Cell Membrane PumpsEndocytosisExocytosis
Endocytosis & Exocytosis
Review Osmosis & Diffusion Here: http://wappingersschools.org/WJH/teachers/science/Jim_Site/asignments/cells/diffusionetc/diffusion_osmosis.html
HomeworkRead pp. 95-100Do questions 1-6 on pg. 100
Read pp. 100-104Do questions 1-6 on pg. 104