tag:blogger.com,1999:blog-51600899485876667742024-03-05T19:07:29.304-08:00MOVEMENT OF SUBSTANCES ACROSS THE PLASMA MEMBRANEChapter 3 Biology F4DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-5160089948587666774.post-22629536461423005582011-08-05T17:25:00.000-07:002011-08-05T17:25:07.730-07:00INTRODUCTION<span style="font-weight:bold;">LEARNING OBJECTIVES:</span><br />
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<span style="font-style:italic;">(i) Analysing the movement of substances across the plasma membrane.<span style="font-weight:bold;"></span></span><br />
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<span style="font-style:italic;">(ii) Understanding the movement of substances across the plasma membrane in everyday life.<span style="font-weight:bold;"></span></span><br />
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<span style="font-style:italic;">(iii) Appreciating the movement of substances across the plasma membrane.<span style="font-weight:bold;"></span></span><br />
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<span style="font-weight:bold;">PRIOR KNOWLEDGE</span><br />
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<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7t64y4qqhJoZaj26vVCBKSaHciuU3YrIND2bCryqYk2DSMGOyDA7MLVxmtRbZ6S1NsjFYSw7GS2MXigCwFeJ7eVVlhqlynQwaPQa6aGLlK_H7duQBj1MCG5GDWZOQHh_KSp-MMSucad8/s1600/animal+cell.gif" imageanchor="1" style="clear:left; float:left;margin-right:1em; margin-bottom:1em"><img border="0" height="301" width="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7t64y4qqhJoZaj26vVCBKSaHciuU3YrIND2bCryqYk2DSMGOyDA7MLVxmtRbZ6S1NsjFYSw7GS2MXigCwFeJ7eVVlhqlynQwaPQa6aGLlK_H7duQBj1MCG5GDWZOQHh_KSp-MMSucad8/s400/animal+cell.gif" /></a></div><br />
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<span style="font-weight:bold;">The structure of an animal cell<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPJXH82U-HJJh_-u8pYNF-5ppjR5kUdwxPBgEJ3atpYzi99Om4YvVx2LlN3fqouAxBYjcxut26L5j8oaROup2TXWmnti9Ivw9dhu8jeGsokVvCvzWdBaMkpOXVDRYawFx7sVjut2OEylQ/s1600/Plant+cell.2.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 400px; height: 228px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPJXH82U-HJJh_-u8pYNF-5ppjR5kUdwxPBgEJ3atpYzi99Om4YvVx2LlN3fqouAxBYjcxut26L5j8oaROup2TXWmnti9Ivw9dhu8jeGsokVvCvzWdBaMkpOXVDRYawFx7sVjut2OEylQ/s400/Plant+cell.2.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5578149283086874962" /></a><br />
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<span style="font-weight:bold;">The structure of a plant cell</span><br />
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<iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/Fzj6TRnXmps?rel=0" frameborder="0" allowfullscreen></iframe><br />
<span style="font-weight:bold;">An Animal Cell Simulation Video</span><br />
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<iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/uohe2V4yOzE?rel=0" frameborder="0" allowfullscreen></iframe><br />
<span style="font-weight:bold;">A plant cell simulation video</span>DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.comtag:blogger.com,1999:blog-5160089948587666774.post-39042156275740649662011-03-01T14:14:00.001-08:002011-03-04T10:30:18.449-08:003.1 MOVEMENT ACROSS THE PLASMA MEMBRANETHE STRUCTURE OF THE PLASMA MEMBRANE<br /><br />1. The Fluid-Mosaic Model of the plasma membrane was proposed by S. Singer and G. Nicolson in 1972. They proposed that membrane proteins are dispersed throughout and inserted into the phospholipid bilayer.<br /><br />2. Pictured as "mosaic" because it has various protein molecules embedded in the phospholipid bilayer. The membrane is "fluid" cause the proteins and phospholipid molecules drift laterally in the membrane.<br /><br />3. Two parts in each phospholipid molecule:<br />(i) a polar head which is hydrophilic ('<span style="font-style:italic;">keen of water</span>')<br />(ii) a pair of non-polar fatty acid tails which are hydrophobic ('<span style="font-style:italic;">hate of water</span>').<br /><br />4. Phospholipids are arranged in bilayer = phospholipid bilayer.<br /><br />5. Types of proteins embedded :<br />(i) <span style="font-style:italic;">pore proteins</span> : has a pore to provide a passage for solutes to pass through the plasma membrane.<br />(ii) <span style="font-style:italic;">carrier proteins</span> :acts as a carrier to carry molecules across the plasma membrane.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjngjjODFidTlecDEm2FoSF7qvxxELloYlZhOYZSP5bdj-ZweWV7Tliq1XI4SLVg0h1j_VK0xnDOECQfmHv4cjTgaTFRf27RmRfZIqPBs4wewt85RKx_WODdrviQgwQT4i12n_ix5URXDE/s1600/fluid-mosaic+model.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 400px; height: 199px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjngjjODFidTlecDEm2FoSF7qvxxELloYlZhOYZSP5bdj-ZweWV7Tliq1XI4SLVg0h1j_VK0xnDOECQfmHv4cjTgaTFRf27RmRfZIqPBs4wewt85RKx_WODdrviQgwQT4i12n_ix5URXDE/s400/fluid-mosaic+model.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579238888537862946" /></a><br /><br /><br /><br />The Fluid-Mosaic Model of the plasma membrane<br /><br /><br /><br /><br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFse-cXFRzA0ZUFsl_aN0xUWf4w8BGskptulU7Ix-k_k53bJYsKYHFE01g-N-lB9O7XcMo-AGsuy5vv1ikSfdvlMktezTpNHM6IysRaj9CzmV6IDDBtvDiaW1g9pPwnNrkg_ss3OqFLFc/s1600/movement+of+lipid.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 196px; height: 121px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgFse-cXFRzA0ZUFsl_aN0xUWf4w8BGskptulU7Ix-k_k53bJYsKYHFE01g-N-lB9O7XcMo-AGsuy5vv1ikSfdvlMktezTpNHM6IysRaj9CzmV6IDDBtvDiaW1g9pPwnNrkg_ss3OqFLFc/s400/movement+of+lipid.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579239056977836738" /></a><br /><br />The movement of a lipid-soluble molecule through the phospholipid bilayer<br /><br /><br /><br /><br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/moPJkCbKjBs?rel=0" frameborder="0" allowfullscreen></iframe><br />A simulation of the plasma membrane structureDR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com1tag:blogger.com,1999:blog-5160089948587666774.post-56628972207923602402011-03-01T13:49:00.001-08:002011-08-05T17:19:07.127-07:00PASSIVE TRANSPORT<br />
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1. Passive transport is the movement of substances across the plasma membrane from a region of high concentration to a region of lower concentration, that is going down a concentration gradient until a <span style="font-style:italic;">dynamic equilibrium achieved</span>.<br />
2. Therefore, this process <span style="font-style:italic;">does not require energy</span>.<br />
3. Substances move across the plasma membrane down the concentration gradient through three different ways:<br />
(a) lipid bilayer<br />
(b) carrier protein<br />
(c) pore protein<br />
4. Substances move freely either through <br />
(a) simple diffusion<br />
(b) osmosis<br />
(c) facilitated diffusion (with the help of carrier proteins or pore proteins)<br />
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<span style="font-style:italic;">A. Simple Diffusion <span style="font-style:italic;">(Resapan Ringkas)</span></span><br />
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1. Molecules diffuse across the plasma membrane down the concentration gradient through the phospholipid bilayer until dinamic equilibrium achieved.<br />
2. Substances involved:<br />
(i) small uncharged polar molecules : oxygen, carbon dioxide, water. Example: exchange of gases between the alveolus and blood capillaries.<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4TlHLZ07NTsYhtgTzHnhBx4CF4hZ81GpGXnZ41dVOGfl18XYDjUi_gv0tGBpKAZGF8k5S_X9lkyUdz1YIOYBVGKAUVjZwYzXxdIkhdXN_ViOXMDZfznYVEgvvIC6MTUoeinEWh3M1-Vw/s1600/gases+exchange.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 222px; height: 156px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg4TlHLZ07NTsYhtgTzHnhBx4CF4hZ81GpGXnZ41dVOGfl18XYDjUi_gv0tGBpKAZGF8k5S_X9lkyUdz1YIOYBVGKAUVjZwYzXxdIkhdXN_ViOXMDZfznYVEgvvIC6MTUoeinEWh3M1-Vw/s400/gases+exchange.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5580297986145831234" /></a><br />
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Gases exchange between the alveolus and blood capillaries<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiU27P331xhmTrsqKwJZ1awYYrdrcrriJz9G9PQmgsuqzSBNmAMN2JbDVn1nZcjSsGeeM0TTlckbxZ4lRhOkbXSXK01d8NEZI0c43n4qWEM5PlvOJ43ZPMrqa6JUSkuaWYZqphyoFAYvGs/s1600/simple+diffusion.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 194px; height: 132px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiU27P331xhmTrsqKwJZ1awYYrdrcrriJz9G9PQmgsuqzSBNmAMN2JbDVn1nZcjSsGeeM0TTlckbxZ4lRhOkbXSXK01d8NEZI0c43n4qWEM5PlvOJ43ZPMrqa6JUSkuaWYZqphyoFAYvGs/s400/simple+diffusion.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579234661779685026" /></a><br />
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The process of simple diffusion<br />
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<iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/aVc_LEuiZ-4?rel=0" frameborder="0" allowfullscreen></iframe><br />
A simulation of simple diffusion process (built by the blogger using the macromedia flash software)<br />
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<span style="font-style:italic;">B. Osmosis</span><br />
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1. Osmosis is the diffusion of water molecules through the plasma membrane or semi-permeable membrane.<br />
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2. The net movement of water molecules is from a region of <span style="font-style:italic;">low solute concentration</span> (high water concentration/dilute solution) to a region of high solute concentration through a semi-permeable membrane.<br />
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3. Example: the absorption of water by root hairs of a plant where the soil has a higher water concentration than the cytoplasm in the root hairs.<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhwoIE-5bmtUYPLp4ij4P3_1SNiBBKs6BmCObqRC4ysVSeXx-rg5bJzzD18D249VZIhQpOzx5mu7bmRYCsG0PLbnf8l9XZeknNQ-Gq8FU82ZCr2QQqA7rdyo_mvxViJ2z_q5yVrRslTbGo/s1600/osmosis.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 158px; height: 381px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhwoIE-5bmtUYPLp4ij4P3_1SNiBBKs6BmCObqRC4ysVSeXx-rg5bJzzD18D249VZIhQpOzx5mu7bmRYCsG0PLbnf8l9XZeknNQ-Gq8FU82ZCr2QQqA7rdyo_mvxViJ2z_q5yVrRslTbGo/s400/osmosis.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579234843751857346" /></a><br />
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The process of osmosis<br />
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<iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/4915MnZulXE?rel=0" frameborder="0" allowfullscreen></iframe><br />
A simulation of osmosis process (built by the blogger using macromedia flash software)<br />
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<span style="font-style:italic;">C. Facilitated Diffusion <span style="font-style:italic;">(Resapan Berbantu)</span></span><br />
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1. Refers to the movement of hydrophilic molecules or ions across the plasma membrane with the help of transport proteins:<br />
(i) transported by binding at the binding sites of carrier proteins (examples: larger uncharged polar molecules like glucose and amino acids). Then carrier proteins change their shapes. After the process, the carrier proteins return back to their original shapes.<br />
(ii) through the pores of pore proteins (examples: small charged molecules like mineral ions).<br />
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2. Examples : transportation of molecules which are not soluble in lipids such as glucose, amino acids and mineral ions through the villus at the ileum.<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidgXC8TqBjtp0EKtJYQz5jCVN6NBVeJe8jBA3kvVNv27ieANKDw2O8Tf-rcbWbyMLW92s-4wCT3qjMP8b3grPZ7Q0Hk3CZqKmAED8qSwYLNWWOA1Me91P4geRATJN0T40_hMJ7fbkSxBg/s1600/carrier+protein.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 101px; height: 400px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidgXC8TqBjtp0EKtJYQz5jCVN6NBVeJe8jBA3kvVNv27ieANKDw2O8Tf-rcbWbyMLW92s-4wCT3qjMP8b3grPZ7Q0Hk3CZqKmAED8qSwYLNWWOA1Me91P4geRATJN0T40_hMJ7fbkSxBg/s400/carrier+protein.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579235052813506738" /></a><br />
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<span style="font-style:italic;">(i) Facilitated diffusion through a carrier protein</span><br />
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<iframe width="480" height="390" src="http://www.youtube.com/embed/jq6tNVcnXm0?rel=0" frameborder="0" allowfullscreen></iframe><br />
A simulation of facilitated diffusion process through a carrier protein (built by the blogger using the Macromedia Flash software)<br />
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<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg9Dk_YmznFbpOaYea7aY1uuSxXuNKzQQepgWL5ddCC0XFVqoKZ54f_waok_ln6oRv7H9NKNIB7vAN5vZgVDIl4BgX5YFu3doN7fs4isDtjJb1BgaW6hzj7LospxB-Qcl6wY6Jfy-ncTf0/s1600/pore+protein.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 205px; height: 167px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg9Dk_YmznFbpOaYea7aY1uuSxXuNKzQQepgWL5ddCC0XFVqoKZ54f_waok_ln6oRv7H9NKNIB7vAN5vZgVDIl4BgX5YFu3doN7fs4isDtjJb1BgaW6hzj7LospxB-Qcl6wY6Jfy-ncTf0/s400/pore+protein.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579235438917548610" /></a><br />
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<span style="font-style:italic;">(ii) Facilitated diffusion through a pore protein</span><br />
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<iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/YYdFixaYX3g?rel=0" frameborder="0" allowfullscreen></iframe><br />
A simulation of facilitated diffusion process through a pore protein (built by the blogger using the Macromedia Flash software)DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com2tag:blogger.com,1999:blog-5160089948587666774.post-13248673423377508412011-03-01T13:37:00.001-08:002011-03-01T13:50:21.887-08:00ACTIVE TRANSPORT<br /><br />1. Movement of molecules or ions against the concentration gradient acroos the plasma membrane.<br />2. Requires both carrier proteins and the expenditure of <span style="font-style:italic;">energy</span> to transport the molecules or ions. The energy for active transport usually comes from <span style="font-style:italic;">ATP (adenosine triphosphate)</span>which is generated during respiration in the mitochondria.<br />3. The carrier protein has an active site which binds to the particular molecule or ion and another active site which binds to the ATP.<br />4. The carrier protein changes shape when the phosphate group from the ATP binds to it.<br />5. Usually, active transport results in the accumulation of or elimination of molecules or ions <span style="font-style:italic;">from the cells</span>.<br />6. Carrier proteins act as <span style="font-style:italic;">pumps</span>.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCBx5WeW16qK3zAtxa27H-1bDDc0kpNRx8zqbmqrLKjPHyzwoYNrG1dkbgMBXUYwan1MNA3wUUyYj36IaTJf6mAcDvewZSr-ekvGW4JMn4j6eG2exU8jOO9lgOud9tYGS6wQeQ6dQkRRA/s1600/active+transport.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 400px; height: 174px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCBx5WeW16qK3zAtxa27H-1bDDc0kpNRx8zqbmqrLKjPHyzwoYNrG1dkbgMBXUYwan1MNA3wUUyYj36IaTJf6mAcDvewZSr-ekvGW4JMn4j6eG2exU8jOO9lgOud9tYGS6wQeQ6dQkRRA/s400/active+transport.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579231197463378674" /></a><br /><br /><br /><br /><span style="font-style:italic;">The Mechanism of Active Transport for Sodium Ions</span>DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com1tag:blogger.com,1999:blog-5160089948587666774.post-32957891482225421932011-02-28T05:52:00.001-08:002011-03-04T11:40:57.847-08:003.2 MOVEMENT OF SUBSTANCE ACROSS THE PLASMA MEMBRANE IN EVERYDAY LIFE<span style="font-weight:bold;">THE EFFECTS OF HYPOTONIC, HYPERTONIC AND ISOTONIC SOLUTIONS ON ANIMAL AND PLANT CELLS</span><br /><br />1. Hypertonic solution is the solution with a higher solute concentration ('hyper': more).<br />2. Hypotonic solution is the solution with a lower solute concentration ('hypo' : less).<br />3. Isotonic solution is the solution in which the concentration of solutes are equal ('iso' : equal).<br /><br /><br /><span style="font-style:italic;">A. PLANT CELLS IN AN ISOTONIC SOLUTION</span><br />1. If a plant cell is immersed in an isotonic solution such as 5% sucrose solution, there is no net movement of water across the plasma membrane.<br />2. Water flows across the membrane at the same rate in both directions.<br />3. The cell's volume and shape remain constant.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgK-9AKOTWgb5o0qA0pDiUIK8HfRGKezFdIBol9uiyUg4PSMwT_efVoPtxJebXA1Ad-Hl5gXtO6fd1fwgxUVydd1JqEDJwFMRJPemeMH06I1sJBNsCMrULIadaF2a06ZLhrOqBshXwsmpo/s1600/isotonic+solution.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 205px; height: 193px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgK-9AKOTWgb5o0qA0pDiUIK8HfRGKezFdIBol9uiyUg4PSMwT_efVoPtxJebXA1Ad-Hl5gXtO6fd1fwgxUVydd1JqEDJwFMRJPemeMH06I1sJBNsCMrULIadaF2a06ZLhrOqBshXwsmpo/s400/isotonic+solution.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5578841471324933586" /></a><br /><br /><br /><br /><span style="font-style:italic;">Effect of Isotonic Solution on a Plant Cell</span><br /><br /><br /><br /><br /><br /><br /><span style="font-style:italic;">B. PLANT CELLS IN A HYPOTONIC SOLUTION</span><br />1. When a plant cell is immersed in a hypotonic solution such as water, water molecules diffuse into the cell by osmosis.<br />2. The vacuole gain water, expands and exerts pressure outwards on the cell wall.<br />3. This pressure is called <span style="font-weight:bold;"><span style="font-style:italic;">turgor pressure</span></span> which cause the plant cell to become turgid.<br />4. The turgidity of the cells give the plant mechanical support.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdZT9zRym_IsBTNFmlFp-nuKhNWJpIE84V7xaq-6cCTEOZkh2GgxPHbsRDxkDKiu8npad3No0-CKVLx3J-JDdCgzfKkq9o7i_zbFAl3vjb0UlCHpoIFmra9PXOWqKdJXJfo5jiVMDb8HQ/s1600/hypotonic+solution.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 238px; height: 169px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgdZT9zRym_IsBTNFmlFp-nuKhNWJpIE84V7xaq-6cCTEOZkh2GgxPHbsRDxkDKiu8npad3No0-CKVLx3J-JDdCgzfKkq9o7i_zbFAl3vjb0UlCHpoIFmra9PXOWqKdJXJfo5jiVMDb8HQ/s400/hypotonic+solution.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5578848018479022002" /></a><br /><br /><br /><br /><span style="font-style:italic;">Effect of Hypotonic Solution on a Plant Cell</span><br /><br /><br /><br /><br /><br /><span style="font-style:italic;">C. PLANT CELLS IN A HYPERTONIC SOLUTION</span><br />1. When a plant cell is placed in a hypertonic solution such as 30% sucrose solution, water molecules diffuses out of the cell by osmosis.<br />2. Water is lost from the vacuole and cytoplasm.<br />3. The vacuole and the cytoplasm shrink. The plasma membrane is pulled away from the cell wall.<br />4. The plant cell becomes <span style="font-weight:bold;"><span style="font-style:italic;">flaccid</span></span> and the plant wilts.<br />5. This process is called <span style="font-weight:bold;"><span style="font-style:italic;">plasmolysis</span></span>.<br />6. If the plasmolysed plant cell is immersed in a hypotonic solution, there is a net movement of water into the cell. The cell will expand and become <span style="font-weight:bold;"><span style="font-style:italic;">turgid</span></span> again.<br />7. This process is called <span style="font-weight:bold;"><span style="font-style:italic;">deplasmolysis</span></span>.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjKOrzYF32WvI05-d39a3wT_Lj3QO8VwxMuEq0LIGgX8TEVIYUf3vrtXLfz-nRFMtwIYNrZcFNPSmusHs1zrSBHgaUcHsAp4yZiCfjvZSFdhgtmiS0ZOmuNkNtw-oJsu_z0fUBDzdzXCLc/s1600/hypertonic+solution.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 220px; height: 237px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjKOrzYF32WvI05-d39a3wT_Lj3QO8VwxMuEq0LIGgX8TEVIYUf3vrtXLfz-nRFMtwIYNrZcFNPSmusHs1zrSBHgaUcHsAp4yZiCfjvZSFdhgtmiS0ZOmuNkNtw-oJsu_z0fUBDzdzXCLc/s400/hypertonic+solution.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5578848371383315202" /></a><br /><br /><br /><br /><br /><br /><span style="font-style:italic;">Effect of Hypertonic Solution on a Plant Cell</span><br /><br /><br /><br /><br /><br /><br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/gYbt7hhIxPo?rel=0" frameborder="0" allowfullscreen></iframe><br /><span style="font-style:italic;">A Simulation of Plasmolysis Process in Onion Cells<br /></span><br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/z6d2jFk0uS4?rel=0" frameborder="0" allowfullscreen></iframe><br /><span style="font-style:italic;">A Simulation of Deplasmolysis Process in Onion Cells</span><br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/H6N1IiJTmnc?rel=0" frameborder="0" allowfullscreen></iframe><br /><span style="font-style:italic;">A Deplasmolysis Process in a Wilt Salad Leaf.</span><br /><br /><br /><br /><span style="font-style:italic;">D. ANIMAL CELLS IN AN ISOTONIC SOLUTION<br /></span><br />1. When animal cells such as red blood cells are immersed in an isotonic solution (0.85% sodium chloride solution), water molecules flow across the plasa membrane at the same rate in both directions.<br />2. There is no net movement of water molecules across the plasma membrane because the concentration in the red blood cells is the same as the concentration in the environment.<br />3. The red blood cells maintain their shape.<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT96f5hJ0WHmFG3IxPDLSVuIz2Y5gqZ5A28IhpUWjgM88eWnvdPwRXyXlydkPBz_KnD9LiFfWqQOA4QzctXgmRsK7sSVIvaf092nHiCW4XikoTKPbHY9m3Ty36ErdrHGzrK0gEoJfPmlM/s1600/isotonic.red+blood+cells.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 238px; height: 123px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiT96f5hJ0WHmFG3IxPDLSVuIz2Y5gqZ5A28IhpUWjgM88eWnvdPwRXyXlydkPBz_KnD9LiFfWqQOA4QzctXgmRsK7sSVIvaf092nHiCW4XikoTKPbHY9m3Ty36ErdrHGzrK0gEoJfPmlM/s400/isotonic.red+blood+cells.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579225276818903266" /></a><br /><br /><br /><br /><br /><br /><br /><br /><span style="font-style:italic;">E. ANIMAL CELLS IN A HYPOTONIC SOLUTION</span><br />1. When red blood cells are placed in a hypotonic solution (distilled water), water molecules diffuse into the red blood cells by osmosis.<br />2. The red blood cells gain water and swell.Finally burst because they have no cell wall.<br />3. The red blood cells undergo <span style="font-style:italic;">haemolysis</span>.<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJcpuJR7eya54DgJtXzm9EizzvAz_q6hCdXPlKgKZta7SRO1rqUKgv_cPMrmmoPf4jt30Z2p7Wc3cz6s65XYCzOvyxqNRNNf6DhbWW1nl1XZy3iFcB9qPS1aTqnq7E6l2e78Rl4d2I2cA/s1600/hypotonic.redblood+cells.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 238px; height: 94px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhJcpuJR7eya54DgJtXzm9EizzvAz_q6hCdXPlKgKZta7SRO1rqUKgv_cPMrmmoPf4jt30Z2p7Wc3cz6s65XYCzOvyxqNRNNf6DhbWW1nl1XZy3iFcB9qPS1aTqnq7E6l2e78Rl4d2I2cA/s400/hypotonic.redblood+cells.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579224964007191138" /></a><br /><br /><br /><br /><br /><br /><span style="font-style:italic;">F. ANIMAL CELLS IN A HYPERTONIC SOLUTION</span><br />1. When red blood cells are placed in a hypertonic solution (4% sodium chloride solution), water molecules diffuse out of the cells by osmosis.<br />2. Water is rapidly lost.<br />3. The red blood cells will shrivel and probably die.<br />4. This process is called <span style="font-style:italic;">crenation</span>.<br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidiLjyYywne4nsjmwtrjYKjTDfHUFn6KwwCqllZAJR8FquoPar-gFjm6GELGGnymc2TUytL_mQQj5u4-SKeWuiM8MTxd2jNix24LHSXKrlyOOhH-hrJgk9MzH7GwAOdSITTRFXEZrOOGk/s1600/hypertonic.rebblood+cells.jpg"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 244px; height: 101px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEidiLjyYywne4nsjmwtrjYKjTDfHUFn6KwwCqllZAJR8FquoPar-gFjm6GELGGnymc2TUytL_mQQj5u4-SKeWuiM8MTxd2jNix24LHSXKrlyOOhH-hrJgk9MzH7GwAOdSITTRFXEZrOOGk/s400/hypertonic.rebblood+cells.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5579225165372793842" /></a><br /><br /><br /><br /><br /><br /><br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/crpeX8nBgJE?rel=0" frameborder="0" allowfullscreen></iframe>DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com2tag:blogger.com,1999:blog-5160089948587666774.post-29676245536258275802011-02-28T02:48:00.001-08:002011-03-04T17:59:54.364-08:00<span style="font-weight:bold;">THE EFFECTS AND APPLICATIONS OF OSMOSIS IN EVERYDAY LIFE</span><br /><br /><span style="font-style:italic;"><span style="font-weight:bold;">(a) Wilting in Plants</span></span><br /><br />1. Excessive use of chemical fertilisers will cause plants to wilt.<br />2. Fertilisers will dissolve in the soil and cause the soil water to be hypertonic to the root cells of the plant.<br />3. As a result, water diffuses out of the root cells by osmosis. Plasmolysis occurs and the plant cells become flaccid, causing the plant to wilt.<br />4. Wilting commonly occurs in non-woody and herbaceous plants.<br />5. The cells in the plant will promptly recover when water is available. However, if the period of plasmolysis is prolonged, a wilted plant will eventually die. <br />6. Shortage of water in soil may also lead to wilting in plants.The dried soil becomes more concentrated or hypertonic. Then the plants lose water by osmosis and plasmolysis takes place. <br /><br /><iframe title="YouTube video player" width="425" height="349" src="http://www.youtube.com/embed/33Rq8p3PCS8?rel=0" frameborder="0" allowfullscreen></iframe><br /><br /><br /><span style="font-style:italic;"><span style="font-weight:bold;">(b) Food preservation</span></span><br /><br />1. The methods of preserving food include drying, pickling, smoking, salting and sugar-curing.<br />2. Preservation of food is based on the concept of osmosis and plasmolysis.<br />3. Most food is preserved by using salt or sugar. Examples:<br />- A fish is preserved by covering it with salt.The moisture around the fish will be hypertonic to the cell of the fish.The water concentration in the cells of the fish exceeds the water concentration outside the fish. Water diffuses out of the fish cells by osmosis. The cells of the fish lose water and undergo crenation. Therefore, the fish can be kept longer.<br />- In preparing pickles of fruits like mango and papaya, the slices of fruits are immersed in a concentrated sugar solution which is hypertonic to the fruit cells. Water diffuses out of the fruit cells by osmosis into the sugar solution. The cells lose water and not conducive for the growth of microorganisms. Therefore, the fruit can last longer.<br /><br /><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQe3zXIhjiAp87lEqGY4EXBsTO0g882X6Q2VZPbmatNB7nnzJ-d4lWXmF3t1n3B7HvUfwDrvcKzihjwymE4scbM9g9yuNp7_qXSrenXwIG0UX7UddLlbKgXo8Zu7Qq4cz0Ysm8vsDxB-c/s1600/jeruk+buah.jpg"><img style="display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 259px; height: 194px;" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQe3zXIhjiAp87lEqGY4EXBsTO0g882X6Q2VZPbmatNB7nnzJ-d4lWXmF3t1n3B7HvUfwDrvcKzihjwymE4scbM9g9yuNp7_qXSrenXwIG0UX7UddLlbKgXo8Zu7Qq4cz0Ysm8vsDxB-c/s400/jeruk+buah.jpg" border="0" alt=""id="BLOGGER_PHOTO_ID_5578737528831626818" /></a>DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com7tag:blogger.com,1999:blog-5160089948587666774.post-20961180647293714112011-02-24T14:02:00.000-08:002011-02-28T01:55:05.247-08:00DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com1tag:blogger.com,1999:blog-5160089948587666774.post-65105445226954857972011-02-24T14:00:00.000-08:002011-02-28T01:53:39.509-08:00DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com0tag:blogger.com,1999:blog-5160089948587666774.post-11842764162585852432011-02-24T13:59:00.000-08:002011-02-28T02:45:34.968-08:003.3 APPRECIATING THE MOVEMENT OF SUBSTANCES ACROSS THE PLASMA MEMBRANE1. The movement of substances across the plasma membrane occur in a continuous and controlled manner for the survival of a cell.<br /><br />2. The plasma membrane which is semi-permeable to different substances acts as a :<br />(i) <span style="font-weight:bold;">gatekeeper</span> which regulate what goes in and out of the cell.<br />(ii)<span style="font-weight:bold;">barrier</span> between the the contents of cells and the external environment.<br /><br />3. Specific substances move across the plasma membrane at certain parts of the membrane.<br />(i) <span style="font-weight:bold;">Oxygen and carbon dioxide</span> move across the <span style="font-weight:bold;">lipid bilayers</span> of the plasma membrane by <span style="font-weight:bold;">simple diffusion</span>.<br />(ii) <span style="font-weight:bold;">Water molecules</span> move across the <span style="font-weight:bold;">lipid bilayers</span> of the plasma membrane by <span style="font-weight:bold;">osmosis</span>.<br />(iii) <span style="font-weight:bold;">Glucose, amino acids and charged ions</span> move across the plasma membrane through the <span style="font-weight:bold;">carrier proteins and pore proteins</span> by <span style="font-weight:bold;">facilitated diffusion</span>.<br />(iv) <span style="font-weight:bold;">Certain molecules and ions which their concentration against the concentration gradient</span> are pumped in or out of the cell through <span style="font-weight:bold;">carrier proteins</span> by using <span style="font-weight:bold;">energy from ATP (adenosine triphosphate)</span>. Example : potassium ions inside the cell and sodium ions outside the cell.<br /><br />4. The degree of fluidity of the plasma membrane depends on the temperature and the present of specific fatty acids and cholesterol.<br /><br />5. To maintain the proper functioning of a plasma membrane and a cell as a whole, it is essential for us to take care of our food and water intake. Drinking sufficient water every day will help to hydrate body cells as well as regulate the osmotic pressure of the blood.<br /><br />6. We should be thankful to God for the phenomenon of movement of substances across the plasma membrane which ensures the survival of the cells.DR. HJH. NORSALIZA BT. HJ. SABUhttp://www.blogger.com/profile/07706849805239044410noreply@blogger.com0