Ch.7 Membrane Structure and
Function structure, Topic Revision
questions \test review with correct
answers a+ pass.
Terms in this set (40)
CHAPTER 7 KEY 7.1 Cellular membranes are fluid mosaics of lipids
CONCEPTS and proteins
7.2 Membrane structure results in selective
permeability
7.3 Passive transport is diffusion of a substance
across a membrane with no energy investment
7.4 Active transport uses energy to move
solutes against their gradients
7.5 Bulk transport across the plasma membrane
occurs by exocytosis and endocytosis
,selective permeability A property of biological
membranes that allows them to
regulate the passage of
substances across them.
amphipathic Molecule that has both a
hydrophilic region and a
hydrophobic region such as a
phosopholipid.
The currently accepted model of
cell membrane structure, which
envisions the membrane as a
fluid mosaic model mosaic of protein molecules
drifting laterally in a fluid bilayer of
phospholipids.
integral protein 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 proteins Protein appendages loosely
bound to the surface of the
membrane and not embedded
in the lipid bilayer.
, membrane carbohydrates that
are covalently bonded to lipids
glycolipid
A protein with one or more
covalently attached
glycoprotein
carbohydrates.
A transmembrane protein that
helps a certain substance or
transport protein class of closely related
substances to cross the
membrane.
aquaporin protein 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.
Each aquaporin allows entry
of up to 3 billion (3 x 10⁹)
water molecules per second,
passing single file through
its central channel, which fits
ten at a time. Without
aquaporins, only a tiny
fraction of these water
molecules would pass
through the same area of
the cell membrane in a
second, so the channel
protein brings about a
tremendous increase in rate.
Function structure, Topic Revision
questions \test review with correct
answers a+ pass.
Terms in this set (40)
CHAPTER 7 KEY 7.1 Cellular membranes are fluid mosaics of lipids
CONCEPTS and proteins
7.2 Membrane structure results in selective
permeability
7.3 Passive transport is diffusion of a substance
across a membrane with no energy investment
7.4 Active transport uses energy to move
solutes against their gradients
7.5 Bulk transport across the plasma membrane
occurs by exocytosis and endocytosis
,selective permeability A property of biological
membranes that allows them to
regulate the passage of
substances across them.
amphipathic Molecule that has both a
hydrophilic region and a
hydrophobic region such as a
phosopholipid.
The currently accepted model of
cell membrane structure, which
envisions the membrane as a
fluid mosaic model mosaic of protein molecules
drifting laterally in a fluid bilayer of
phospholipids.
integral protein 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 proteins Protein appendages loosely
bound to the surface of the
membrane and not embedded
in the lipid bilayer.
, membrane carbohydrates that
are covalently bonded to lipids
glycolipid
A protein with one or more
covalently attached
glycoprotein
carbohydrates.
A transmembrane protein that
helps a certain substance or
transport protein class of closely related
substances to cross the
membrane.
aquaporin protein 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.
Each aquaporin allows entry
of up to 3 billion (3 x 10⁹)
water molecules per second,
passing single file through
its central channel, which fits
ten at a time. Without
aquaporins, only a tiny
fraction of these water
molecules would pass
through the same area of
the cell membrane in a
second, so the channel
protein brings about a
tremendous increase in rate.
