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The fluid mosaic model of the membrane describes the membrane as
a. containing a significant quantity of water in the interior.
b. composed of fluid phospholipids on the outside and protein on
the inside.
c. composed of protein on the outside and fluid phospholipids on
the inside.
d. made of proteins and lipids that can freely move.
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What chemical property characterizes the interior of the
phospholipid bilayer?
a. It is hydrophobic. c. It is polar.
b. It is hydrophilic. d. It is saturated.
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The transmembrane domain of an integral membrane protein
a. is composed of hydrophobic amino acids.
b. often forms an α-helical structure.
c. can cross the membrane multiple times.
d. All of the choices are correct.
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The specific function of a membrane within a cell is determined by the
a. degree of saturation of the fatty acids within the phospholipid
bilayer.
b. location of the membrane within the cell.
c. presence of lipid rafts and cholesterol.
d. type and number of membrane proteins.
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The movement of water across a membrane is dependent on
a. the solvent concentration.
b. the solute concentration.
c. the presence of carrier proteins.
d. membrane potential.
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If a cell is in an isotonic environment, then
a. the cell will gain water and burst.
b. no water will move across the membrane.
c. the cell will lose water and shrink.
d. osmosis still occurs, but there is no net gain or loss of
cell volume.
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Which of the following is NOT a mechanism for bringing material
into a cell?
a. Exocytosis c. Pinocytosis
b. Endocytosis d. Phagocytosis
