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Which of the following statements about a typical plasma membrane is correct?
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The sides of the plasma membrane that face the cytoplasm and the outside of the cell have different lipid and protein composition.
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Which of the following best describes the structure of a biological membrane?
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Two layers of phospholipids with proteins either crossing the layers or on the surface of the layers
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The permeability of a biological membrane to a specific solute may depend on which of the following?
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The size and polarity of the solute; the types of transport proteins in the membrane
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Which of the following is least likely to be important in holding the components of a biological membrane together?
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Covalent interactions between the phospholipid and protein components of the membrane
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Which of the following statements about osmosis is incorrect?
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Osmosis is the diffusion of water from a region of higher water concentration to a region of lower water concentration.
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In facilitated diffusion, what is the role of the transport protein?
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Transport proteins provide a hydrophilic route for the solute to cross the membrane.
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If the concentration of calcium in the cytoplasm is 2.0 mM and the concentration of calcium in the surrounding fluid is 0.1 mM, how could the cell increase the concentration of calcium in the cytoplasm?
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Active transport
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The movement of glucose into a cell against a concentration gradient is most likely to be accomplished by which of the following?
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Cotransport of the glucose with a proton or sodium ion that was pumped across the membrane using the energy of ATP hydrolysis
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Active and passive transport of solutes across a membrane typically differ in which of the following ways?
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Active transport is usually against the concentration gradient of the solute, whereas passive transport is always down the concentration gradient of the solute; Active transport always involves the utilization of cellular energy, whereas passive transport does not require cellular energy; Active transport always requires the use of transport proteins, but passive transport can sometimes be accomplished without a protein.
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Which of the following does not correctly describe some aspect of either exocytosis or endocytosis?
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Both endocytosis and exocytosis involve active transport.
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