PREP SCRIPT FULL QUESTION SET APPROVED
◉ Plasma Membrane. Answer: The _________ _______________ is the
boundary that separates the living cell from its surroundings.
◉ Selective Permiability. Answer: The plasma membrane exhibits
__________ _______________, allowing some substances to cross it more
easily than others.
◉ Living cell, surroundings. Answer: The plasma membrane is the
boundary that separates the ____________ ________ from its ___________.
◉ Amphipathic Molecules. Answer: Phospholipids are ____________
______________, containing hydrophobic and hydrophilic regions
◉ Phospholipids. Answer: _________________ are amphipathic
molecules, containing hydrophobic and hydrophilic regions
◉ Hugh Davson, James Danielli. Answer: In 1935, _______ _________ and
_________ ___________ proposed a sandwich model in which the
phospholipid bilayer lies between two layers of globular proteins
,◉ Sandwich Model. Answer: In 1935, Hugh Davson and James
Danielli proposed a _____________ ___________ in which the phospholipid
bilayer lies between two layers of globular proteins
◉ Fluid Mosaic Model. Answer: Freeze-fracture studies of the
plasma membrane supported the ___________ ___________ __________.
◉ Freeze-fracture. Answer: ___________ ___________ is a specialized
preparation technique that splits a membrane along the middle of
the phospholipid bilayer
◉ Fluid State, Solid State. Answer: As temperatures cool, membranes
switch from a _______ _________ to a __________ __________.
◉ Unsaturated fatty acids, saturated fatty acids. Answer: Membranes
rich in ______________ ________ ________ are more fluid than those rich in
_______________ _______ ______.
◉ Fluid. Answer: Membranes must be ________ to work properly
◉ Steroid cholesterol. Answer: The _________ ____________ has different
effects on membrane fluidity at different temperatures
,◉ Warm. Answer: At _________ temperatures, cholesterol restrains
movement of phospholipids
◉ cool. Answer: At ________ temperatures, it maintains fluidity by
preventing tight packing
◉ Membrane. Answer: A ______________ is a collage of different
proteins embedded in the fluid matrix of the lipid bilayer
◉ Proteins. Answer: _________ determine most of the membrane's
specific functions
◉ Peripheral proteins. Answer: __________ ___________ are bound to the
surface of the membrane
◉ Transmembrane proteins. Answer: Integral proteins that span the
membrane are called _______________________ ________________.
◉ Integral proteins. Answer: __________ __________ that span the
membrane are called transmembrane proteins
◉ Integral proteins. Answer: ______________ _____________ penetrate the
hydrophobic core
, ◉ Integral protein. Answer: The hydrophobic regions of an
______________ ____________ consist of one or more stretches of nonpolar
amino acids, often coiled into alpha helices
◉ ok. Answer: Six major functions of membrane proteins:
Transport, Enzymatic activity, Signal transduction, Cell-cell
recognition, intercellular joining, and Attachment to the
cytoskeleton and extracellular matrix (ECM)
◉ lipids, proteins. Answer: Membrane carbohydrates may be
covalently bonded to _________ (forming glycolipids) or more
commonly to ___________ (forming glycoproteins)
◉ species, individuals, cell types. Answer: Carbohydrates on the
external side of the plasma membrane vary among __________,
____________, and even _______ _________ in an individual.
◉ Membranes. Answer: __________________ have distinct inside and
outside faces
◉ ER, Golgi apparatus. Answer: The asymmetrical distribution of
proteins, lipids, and associated carbohydrates in the plasma
membrane is determined when the membrane is built by the
_________ and ___________ _________________.