3 transporters including integral proteins that allow

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3. transporters, including: Integral proteins that allow ions or molecules to move across theplasma membrane-Hydrophilic regions faces inward; charge determines molecules that can pass througha. channels (describe) : integral MP that forms a channel. Charge of the hydrophilic portiondictates which ions can pass through.b. carriers (describe) : move ions or molecules across the plasma membranec. ATP pumps (describe): transports ions or molecules across the membrane with the aid of ATP4. receptors (describe): Proteins or glycoproteins in membranes with an exposed receptor site-Can attach to specific chemical signal molecules and act as an intercellular communicationsystem-Ligand can attach only to cells with tht specific receptor5. enzymes (describe) : Some membrane proteins act as enzymes-Catalyze reactions at outer/inner surface of plasma membrane-Surface cells of small intestine produce enzymes that digest dipeptidesMovement through the PM on powerpoint video3.6 MOVEMENT THROUGH THE PLASMA MEMBRANE (Transport mechanisms)Passive: does not require energy-Diffusion, Osmosis, Facilitated diffusion1. Diffusion is … - a net movement of solutes from areas of higher concentration to areas oflowerconcentration (down a concentration gradient) – at equilibrium, net movement stopsActive membrane transport: requires energy:-Active, Secondary active, …..Factors influencing diffusion…FactorsTime for diffusionRate of diffusionIncreased distanceIncreasesDecreases
Increased size of gradientDecreasesIncreasesIncreased size of moleculesIncreasesDecreasesIncreased temperatureDecreasesIncreasesIncreased viscosityIncreasesDecreasesSummarize on your own:-1. Distance: larger distance= slower rate of diffusion-2. Magnitude: high conc gradient= more solute particles moving-3. Size of molecules: smaller molecules diffuse faster-4. Temperature: increased temp. increases speed of movement-5. Viscosity: molecules move slower in a more viscous solutionThe rate of diffusion increases with ……._____________ in distance_____________ in the concentration gradient,______________ in temperature ______________in molecular size, and ______________in viscosity.- Particles can only diffuse through the plasma membrane if theyi. are soluble in _________________________, ORii. have specific ________________________ imbedded in the membrane.2. Osmosis is …- Diffusion of water across a selectively permeable membrane, such as through the cellsof the kidney tubules.- Water moves from an area of low conc to an area of high conc of solute.- DEFINE …a. osmotic pressure: force required to prevent water from moving across a membrane by osmosis.-The greater the conc of a solution, the greater the water will want to go towards that solution,leads to a greater osmotic pressure must be to prevent osmosis.?b. Isosmotic solutions: have same concentration of solute particlesc. Hyperosmotic solutions: have a greater concentration of solute particlesd. Hyposmotic solutions: have a lower concentration of solute particlese. Isotonic: solute concentration is same the concentration of a cell.f. Hypertonic: solute concentration is ___________________than the concentration of a cell.

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Term
Fall
Professor
NishiBryska

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