CAMPBELL BIOLOGY: NINTH EDITION - CHAPTER 7:
MEMBRANE STRUCTURE AND FUNCTION | YOUR
SHORTCUT TO SUCCESS | TRUSTED, TESTED, AND
TRUE!
Selective permeability - Answer: a property of biological membranes that allows them to
regulate the passage of substances across them
Amphipathic - Answer: having both a hydrophilic region and a hydrophobic region
Fluid mosaic model - Answer: the currently accepted model of cell membrane structure,
which envisions the membrane as a mosaic of protein molecules drifting laterally in a
fluid bilayer of phospholipids.
Integral protein - Answer: a transmembrane protein with hydrophobic regions that
extend into and often completely span the hydrophobic interior of the membrane and
with hydrophilic regions in contact with the aqueous solution on one or both sides of the
membrane (or lining the channel in the case of a channel protein).
Peripheral protein - Answer: a protein loosely bound to surface of a membrane or to
part of an integral protein and not embedded in the lipid bilayer
Glycolipid - Answer: a lipid with one or more covalently attached carbohydrates
Glycoprotein - Answer: a protein with one or more covalently attached carbohydrates
Transport protein - Answer: a transmembrane protein that helps a certain substance or
class of closely related substances to cross the membrane
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
, Aquaporin - Answer: a channel protein in the plasma membrane of a plant, animal or
microorganism cell that specifically facilitates osmosis, the diffusion of free water across
the membrane
Diffusion - Answer: the spontaneous movement of a substance down its concentration
or electrochemical gradient, from a region where it is more concentrated to a region
where it is less concentrated.
Concentration gradient - Answer: a region along which the density of a chemical
substance increases or decreases.
Passive transport - Answer: the diffusion of a substance across a biological membrane
with no expenditure of energy
Osmosis - Answer: the diffusion of free water across a selectively permeable
membrane
Tonicity - Answer: the ability of a solution surrounding a cell to cause that cell to gain or
loose water.
Isotonic - Answer: referring to a soultion that, when surrounding a cell, causes no net
movement of water into or out of a cell
Hypertonic - Answer: referring to a solution that, when surrounding a cell, will cause the
cell to lose water
Hypotonic - Answer: referring to a solution that, when surrounding a cell, will cause the
cell to take up water.
Osmoregulation - Answer: regulation of solute concentrations and water balance by a
cell or organism
2
APPHIA - Crafted with Care and Precision for Academic Excellence.
MEMBRANE STRUCTURE AND FUNCTION | YOUR
SHORTCUT TO SUCCESS | TRUSTED, TESTED, AND
TRUE!
Selective permeability - Answer: a property of biological membranes that allows them to
regulate the passage of substances across them
Amphipathic - Answer: having both a hydrophilic region and a hydrophobic region
Fluid mosaic model - Answer: the currently accepted model of cell membrane structure,
which envisions the membrane as a mosaic of protein molecules drifting laterally in a
fluid bilayer of phospholipids.
Integral protein - Answer: a transmembrane protein with hydrophobic regions that
extend into and often completely span the hydrophobic interior of the membrane and
with hydrophilic regions in contact with the aqueous solution on one or both sides of the
membrane (or lining the channel in the case of a channel protein).
Peripheral protein - Answer: a protein loosely bound to surface of a membrane or to
part of an integral protein and not embedded in the lipid bilayer
Glycolipid - Answer: a lipid with one or more covalently attached carbohydrates
Glycoprotein - Answer: a protein with one or more covalently attached carbohydrates
Transport protein - Answer: a transmembrane protein that helps a certain substance or
class of closely related substances to cross the membrane
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
, Aquaporin - Answer: a channel protein in the plasma membrane of a plant, animal or
microorganism cell that specifically facilitates osmosis, the diffusion of free water across
the membrane
Diffusion - Answer: the spontaneous movement of a substance down its concentration
or electrochemical gradient, from a region where it is more concentrated to a region
where it is less concentrated.
Concentration gradient - Answer: a region along which the density of a chemical
substance increases or decreases.
Passive transport - Answer: the diffusion of a substance across a biological membrane
with no expenditure of energy
Osmosis - Answer: the diffusion of free water across a selectively permeable
membrane
Tonicity - Answer: the ability of a solution surrounding a cell to cause that cell to gain or
loose water.
Isotonic - Answer: referring to a soultion that, when surrounding a cell, causes no net
movement of water into or out of a cell
Hypertonic - Answer: referring to a solution that, when surrounding a cell, will cause the
cell to lose water
Hypotonic - Answer: referring to a solution that, when surrounding a cell, will cause the
cell to take up water.
Osmoregulation - Answer: regulation of solute concentrations and water balance by a
cell or organism
2
APPHIA - Crafted with Care and Precision for Academic Excellence.
