membranes chapter 05. membranes chapter 5 outline membrane models fluid-mosaic plasma membrane...
TRANSCRIPT
![Page 1: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/1.jpg)
MembranesChapter
05
![Page 2: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/2.jpg)
Membranes 2
Chapter 5 Outline
Membrane ModelsFluid-Mosaic
Plasma Membrane Structure and FunctionPhospholipidsProteins
Plasma Membrane PermeabilityDiffusionOsmosisTransport Via Carrier Proteins
Cell Surface Modifications
![Page 3: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/3.jpg)
Membranes 3Structure and Function:The Phospholipid Bilayer
The plasma membrane is common to all cellsSeparates:
Internal living cytoplasmic fromExternal environment of cell
Phospholipid bilayer:External surface lined with hydrophilic polar heads
Cytoplasmic surface lined with hydrophilic polar heads
Nonpolar, hydrophobic, fatty-acid tails sandwiched in between
![Page 4: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/4.jpg)
Membranes 4
Unit Membrane
![Page 5: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/5.jpg)
Membranes 5
Membrane Models
Fluid-Mosaic ModelThree components:
Basic membrane referred to as phospholipid bilayer
Protein molecules Float around like icebergs on a seaMembrane proteins may be peripheral or integralPeripheral proteins are found on the inner membrane surface
Integral proteins are partially or wholly embedded (transmembrane) in the membrane
Some have carbohydrate chains attachedCholesterol
![Page 6: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/6.jpg)
Membranes 6
Membrane Models:Unit Membrane vs. Fluid Mosaic Model
![Page 7: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/7.jpg)
Membranes 7
The Fluid Mosaic Model
![Page 8: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/8.jpg)
Membranes 8
Phospholipid & CholesterolMolecules
![Page 9: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/9.jpg)
Membranes 9Transmembrane Proteins
![Page 10: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/10.jpg)
Membranes 10
Lateral Migration ofMembrane Proteins
![Page 11: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/11.jpg)
Membranes 11
Functions of Membrane Proteins
Channel Proteins: Tubular Allow passage of molecules through membrane
Carrier Proteins: Combine with substance to be transported Assist passage of molecules through membrane
Cell Recognition Proteins: Provides unique chemical ID for cells Help body recognize foreign substances
Receptor Proteins: Binds with messenger molecule Causes cell to respond to message
Enzymatic Proteins: Carry out metabolic reactions directly
![Page 12: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/12.jpg)
Membranes 12
Membrane Protein Diversity
![Page 13: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/13.jpg)
Membranes 13Types of Transport:Active vs. Passive
Plasma membrane is differentially (selectively) permeable Allows some material to pass Inhibits passage of other materials
Passive Transport:No ATP requirementMolecules follow concentration gradient
Active TransportRequires carrier proteinRequires energy in form of ATP
![Page 14: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/14.jpg)
Membranes 14Types of Membrane Transport:Overview
![Page 15: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/15.jpg)
Membranes 15Types of Transport:Diffusion
A solution consists of:A solvent (liquid) , andA solute (dissolved solid)
DiffusionNet movement of solute molecules down a concentration gradient
Molecules both ways along gradientMore move from high to low concentration than vice versa
Equilibrium:When NET change stops Solute concentration uniform – no gradient
![Page 16: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/16.jpg)
Membranes 16Types of Membrane Transport:Diffusion
![Page 17: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/17.jpg)
Membranes 17Types of Membrane Transport:Diffusion Across Lung
![Page 18: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/18.jpg)
Membranes 18Types of Transport:Osmosis
Osmosis: Special case of diffusion Focuses on solvent (water) movement rather than solute
Diffusion of water across a differentially (selectively) permeable membrane Solute concentration on one side high, but water
concentration low Solute concentration on other side low, but water
concentration high Water diffuses both ways across membrane but solute can’t
Net movement of water is toward low water (high solute) concentration
Osmotic pressure is the pressure that develops due to osmosis
![Page 19: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/19.jpg)
Membranes 19Types of Membrane Transport:Osmosis
![Page 20: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/20.jpg)
Membranes 20Types of Transport:Osmosis
Isotonic SolutionSolute and water concentrations equal on both sides of membrane
Hypotonic Solution Concentration of solute lower than on other sideCells placed in a hypotonic solution will swellMay cause cells to break – Lysis
Hypertonic SolutionConcentration of solute higher than on other sideCells placed in a hypertonic solution will shrink – Plasmolysis
![Page 21: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/21.jpg)
Membranes 21
Osmotic Effects on Cells
![Page 22: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/22.jpg)
Membranes 22Types of Transport:Carrier Proteins
Facilitated Transport Small moleculesCan’t get through membrane lipidsCombine with carrier proteins Follow concentration gradient
Active Transport Small moleculesMove against concentration gradientCombining with carrier proteinsRequires energy
![Page 23: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/23.jpg)
Membranes 23Types of Membrane Transport:Facilitated Transport
![Page 24: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/24.jpg)
Membranes 24
Facilitated Transport:The Sodium-Potassium Pump
![Page 25: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/25.jpg)
Membranes 25Types of Transport:Membrane-Assisted Transport
Macromolecules transported into or out of the cell inside vesiclesExocytosis – Vesicles fuse with plasma membrane and secrete contents
Endocytosis – Cells engulf substances into pouch which becomes a vesicle Phagocytosis – Large, solid material into vesicle Pinocytosis – Liquid or small, solid particles go into vesicleReceptor-Mediated – Specific form of pinocytosis using a coated pit
![Page 26: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/26.jpg)
Membranes 26Membrane-Assisted Transport:Exocytosis
![Page 27: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/27.jpg)
Membranes 27Membrane-Assisted Transport:Three Types of Endocytosis
![Page 28: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/28.jpg)
Membranes 28Cell Surface Modifications:Junctions
Cell Surfaces in AnimalsJunctions Between Cells
Adhesion Junctions Intercellular filaments between cells
Tight JunctionsForm impermeable barriers
Gap JunctionsPlasma membrane channels are joined (allows communication)
![Page 29: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/29.jpg)
Membranes 29
Cell-Surface Modifications:Junctions
![Page 30: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/30.jpg)
Membranes 30
Cell Surface Modifications
Extracellular MatrixExternal meshwork of polysaccharides and proteins
Found in close association with the cell that produced them
Plant Cell WallsPlants have freely permeable cell wall, with cellulose as the main component Plasmodesmata penetrate cell wall Each contains a strand of cytoplasmAllow passage of material between cells
![Page 31: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/31.jpg)
Membranes 31
Cell-Surface Modifications:Extracellular Matrix
![Page 32: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/32.jpg)
Membranes 32
Cell-Surface Modifications:Plasmodesmata
![Page 33: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/33.jpg)
Membranes 33
Review
Membrane ModelsFluid-Mosaic
Plasma Membrane Structure and FunctionProtein FunctionsPlasma Membrane PermeabilityDiffusion
Osmosis
Transport Via Carrier Proteins
Cell Surface Modifications
![Page 34: Membranes Chapter 05. Membranes Chapter 5 Outline Membrane Models Fluid-Mosaic Plasma Membrane Structure and Function Phospholipids Proteins Plasma](https://reader035.vdocument.in/reader035/viewer/2022062409/5697c0301a28abf838cdae53/html5/thumbnails/34.jpg)
MembranesEnding Slide Chapter
05