Plasma Membrane SB0014 PDF

S B 001 4 CE L L DI VE R S I TY, R E P R O DUCTI O N, E CO L O GY AND DE VE L O P ME NT Plasma Membrane y.m du &...

S B 001 4 CE L L DI VE R S I TY, R E P R O DUCTI O N, E CO L O GY AND DE VE L O P ME NT Plasma Membrane y.m du & e s. um Movement of di @ Molecules ak m MAKDI MASNODDIN [email protected] room 34, FSSA/Pejabat PPST Fluid Mosaic Model Components of plasma membrane, Permeability of lipid bilayer, Transport proteins y.m Transport of Small Molecules du Diffusion, Passive transport, Osmosis, Facilitated Course e s. diffusion, Active transport Outline um Transport of Large Molecules @ di Exocytosis, Endocytosis ak m Course Outcome At the end of the study, student should be able to state and define concepts and principles in biology, and transport across membrane  y.m a membrane is a fluid structure du with a “mosaic” (lipid bilayer) of e s. um various proteins embedded in it di @ ak m Fluid Mosaic Model  Freeze-fracture experiment y.m du e s. um @ di Singer and Nicloson ak (1972) proposed the m fluid mosaic model to describe the structure of the cell membrane  m ak di @ um s. edu.m y  m ak di @ um s. edu.m y m ak di @ um s. edu.m y  m ak di @ um s. edu.m y  m Phospholipids can ak di @ um s. edu.m y fluidity of the phospholipid bilayer m ak di @ um s. edu.m y m ak di @ um s. edu.m y  y.m due s. um @ di ak m in plant cells similar compound, sterols fulfil a similar function. m ak di @ um s. edu.m y In the lipid bilayer, many different proteins are often grouped together. y.m du e s. um @ di ak Transport Enzymatic Signal m Activity transduction Membrane proteins determine most of the membrane’s specific functions y.m edu s. um @ di ak Cell-cell Intercellular Attachment to m recognition joining the cytoskeleton and extracellular matrix (ECM) m ak di @ um s. edu.m y m DIFFER ak di @ um s. edu.m y DIFFER m ak di @ um s. edu.m y  y.m e du s. um @ di Uraki, R., Kawaoka, Y. Host glycolipids in SARS-CoV-2 entry. Nat Chem Biol 18, 6–7 (2022) ak m  y.m due s. um @ di ak m can dissolve in the lipid bilayer and pass through the membrane rapidly Fluid Mosaic Model Components of plasma membrane, Permeability of lipid bilayer, Transport proteins y.m Transport of Small Molecules du Diffusion, Passive transport, Osmosis, Facilitated Course e s. diffusion, Active transport Outline um Transport of Large Molecules @ di Exocytosis, Endocytosis ak m Course Outcome At the end of the study, student should be able to state and define concepts and principles in biology, and transport across membrane m ak di @ um s. edu.m y  m ak di @ um s. edu.m y  PASSIVE TRANSPORT ▪ Simple Diffusion ▪ Facilitated Diffusion y.m due s. um @ di ak m ACTIVE TRANSPORT  Simple Diffusion: The tendency for molecules to spread out evenly into the available space y.m e du s. um @ di ak m Random movement Directional Dynamic Equilibrium Each molecule But the diffusion of a The same number of moves randomly set of molecules may molecules pass through the be directional membrane in both directions. m ak di @ um s. edu.m y  Transport proteins speed up the passive transport of molecules 10 20 40 30 0 Passive transport m ak di @ protein Passive transport via um s. edu.m y  Channel protein provide pathways that let a specific molecule or ion to y cross the membrane.m due s. um @ Carrier protein di undergo a structural ak changes that allows m the solute-binding site to be moved across the membrane.  OSMOSIS The facilitated diffusion of water molecules across a y selectively permeable.m membrane due s. um @ di EQUILIBRIUM ak m water diffuses from the region of lower solute concentration to the region of higher solute concentration  m ak di @ um s. edu.m y water diffuses from the region of lower solute concentration to the region of higher solute concentration. ▪ ▪ ▪ ▪ m ak di @ um s. edu ▪ ▪.m y m ak di @ um s. edu.m y  ▪ ▪ m ▪ ▪ ▪ ak di @ um s. edu.m y ▪ ▪ ▪ m ak di @ um s. edu.m y A mechanism of adaption for life in such environments is required m ak di @ um s. edu.m y  EXAMPLES The protist Paramecium and Chlamydomonas (green alga) which is hypertonic to its pond (hypotonic) water y.m environment, has a du contractile vacuole that acts as a pump e s. um @ di CONTRACTILE ak VACUOLE m A specialized organelle in the cell that collects and pumps water out with regular contractions. m ak di @ um s. edu.m y  Figure 7.18-6 EXTRACELLULAR [Na+] high Na+ FLUID [K+] low Na+ Na+ Na+ Na+ Na+ Na+ Na+ y.m [Na+] low ATP CYTOPLASM Na+ P du [K+] high P 1 2 ADP 3 e s. um @ K+ di ak m K+ K+ K+ K+ P 6 K+ 5 4 Pi m ak di @ um s. edu.m y  ▪ ▪ m ak di @ um s. edu.m y Chemical Force + Electrical Force = Electrochemical gradient m ak di @ um s. edu.m y Fluid Mosaic Model Components of plasma membrane, Permeability of lipid bilayer, Transport proteins y.m Transport of Small Molecules du Diffusion, Passive transport, Osmosis, Facilitated Course e s. diffusion, Active transport Outline um Transport of Large Molecules @ di Exocytosis, Endocytosis ak m Course Outcome At the end of the study, student should be able to state and define concepts and principles in biology, and transport across membrane m ak di @ um s. edu.m y m ak di @ um s. edu.m y m ak di @ um s. edu.m y  m ak di @ um s. e ▪ ▪ ▪ du.m y Food vacuole formation m ak di @ um s. edu.m y Vesicle fuse and release m ak di @ um s. edu.m y Ligand binding trigger vesicle formation m ak di @ um s. edu.m y  y.m THANK du YOU e Main References s. Campbell Biology (Campbell um Biology Series) @ di Question and Discussion ak [email protected] m