31.What happens to the ATP after it binds to the protein?Active transportmoves molecules against a concentration gradient, where as in passivetransport molecules move down a concentration gradient. To move them,requires energy32.The type of transport shown in Model 4 is calledactive transport, whilediFusion andfacilitated diFusion are calledpassive transport. Giventhe direction of the concentrationgradient in active and passivetransport examples, explain why active transport requires energy inputby the cell.33. With your group, complete the table below to show the diFerencebetween active and passive transport.ActiveTransportPassive TransportDifusionFacilitatedDifusionRequires energyinputby the cellMolecules movealong aconcentrationgradientMolecules moveagainst aconcentrationgradientAlways involveschannelMolecules move along(down) a concentrationgradientActive transportMoves moleculesagainst (up)aconcentration gradientdiFusionAlways involveschannel(membrane-spanning)proteins±aciliteddiFusionMolecules passbetweenthephospholipidsMembrane Structure and ±unction7
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View Full DocumentMoves ions like Na+and K+Active transportMoves large moleculesdifusionMoves small nonpolarand polar moleculesFaciliteddifusion34. With your group develop a de±nition ²or active transport.Extension Questions35.Given the in²ormation in the graph, which type o² cell transport would bebest to movesubstances into or out o² the cell quickly?Active transport36.Which type o² transport would be the best i² the cell needs to respond toa sudden concentration gradient diference?difusion37.Why would the line representing ²acilitated difusion level of as theconcentration gets higher, while the line representing difusion continuesto go up at a steady rate? FD relies on proteins, the number o² proteinswill limit how ²ast the substance can be moved.38.Why does active transport, on the same graph, start of with such a highinitial rate compared to difusion and ²acilitated difusion? Activetransport does not depend on a concentration gradient, only a supply o²<span>energy.</span>
