Module 3 Exam: Fund of Cell Biology UPDATED
ACTUAL Questions and CORRECT Answers
Functional plasma membrane - CORRECT ANSWER -A membrane in mammals that creates a barrier between
internal and external environments, controls transport, receives signals, and remains flexible for movement and growth
Endomembrane system - CORRECT ANSWER -A network of connected lipid bilayer membranes inside
eukaryotic cells including the ER, Golgi, lysosomes, nucleus, and peroxisomes
Compartmentalization - CORRECT ANSWER -The division of the cell into specialized membrane-bound regions
with distinct functions
Smooth endoplasmic reticulum (smooth ER) - CORRECT ANSWER -Organelle where phospholipids are
synthesized for cellular membranes
Vesicle budding - CORRECT ANSWER -The process where a membrane pinches off to form a transport vesicle
Vesicle fusion - CORRECT ANSWER -The merging of a vesicle membrane with another membrane to deliver
contents
Phospholipid bilayer - CORRECT ANSWER -Double layer of phospholipids forming the basic structure of cell
membranes
Phospholipid - CORRECT ANSWER -Amphipathic lipid containing a hydrophilic head and hydrophobic fatty acid
tails
Hydrophilic - CORRECT ANSWER -Water-attracting or polar
Hydrophobic - CORRECT ANSWER -Water-repelling or nonpolar
Phosphatidylcholine - CORRECT ANSWER -Most common phospholipid found in mammalian cell membranes
Amphipathic - CORRECT ANSWER -Having both hydrophilic and hydrophobic regions
Cholesterol - CORRECT ANSWER -Membrane lipid that stabilizes membrane fluidity at extreme temperatures
Glycolipid - CORRECT ANSWER -Lipid with attached carbohydrate important for cell recognition and immune
response
Membrane fluidity - CORRECT ANSWER -The ability of lipids and proteins in a membrane to move within the
bilayer
Lateral diffusion - CORRECT ANSWER -Movement of lipids or proteins side-to-side within a membrane layer
Flip-flop movement - CORRECT ANSWER -Movement of lipids from one monolayer of the membrane to the
other
Scramblase - CORRECT ANSWER -ER enzyme that randomly transfers phospholipids between monolayers to
maintain balanced growth
Flippase - CORRECT ANSWER -Golgi enzyme that selectively transfers specific phospholipids between
membrane layers
Membrane asymmetry - CORRECT ANSWER -Unequal distribution of lipids and proteins between the two sides
of a membrane
Cytosolic side - CORRECT ANSWER -The membrane surface facing the cytoplasm
, Non-cytosolic side - CORRECT ANSWER -The membrane surface facing away from the cytoplasm or toward
organelle interiors/extracellular space
Membrane polarity - CORRECT ANSWER -The maintenance of distinct cytosolic and non-cytosolic membrane
orientations during vesicle transport
Membrane protein - CORRECT ANSWER -Protein associated with or embedded in the lipid bilayer
Transport protein - CORRECT ANSWER -Membrane protein that moves substances across the membrane
Channel protein - CORRECT ANSWER -Transport protein forming a pore that allows substances to move down
their electrochemical gradient
Transporter - CORRECT ANSWER -Protein that changes shape to move cargo across a membrane
Transmembrane protein - CORRECT ANSWER -Protein that spans the entire lipid bilayer
Monolayer-associated protein - CORRECT ANSWER -Protein embedded in only one membrane layer
Lipid-linked protein - CORRECT ANSWER -Protein covalently attached to a lipid in the membrane
Protein-attached protein - CORRECT ANSWER -Protein indirectly attached to the membrane through another
membrane protein
Alpha helix - CORRECT ANSWER -Common protein secondary structure stabilized by hydrogen bonds
Hydrophobic alpha helix - CORRECT ANSWER -Alpha helix with nonpolar side chains that can interact with the
membrane interior
Hydrophilic channel - CORRECT ANSWER -Passage formed by membrane proteins allowing polar molecules to
cross membranes
Cell cortex - CORRECT ANSWER -Meshwork of proteins attached to the cytosolic side of the plasma membrane
that supports cell shape
Extracellular matrix (ECM) - CORRECT ANSWER -Network of proteins and carbohydrates outside the cell
providing support and signaling
Diffusion barrier - CORRECT ANSWER -Structure such as a tight junction that restricts movement of membrane
proteins and lipids
Tight junction - CORRECT ANSWER -Cell junction that prevents diffusion of membrane components between
regions
Apical surface - CORRECT ANSWER -Top region of an epithelial cell facing outward or toward a lumen
Basal surface - CORRECT ANSWER -Bottom region of an epithelial cell attached to underlying tissue
Glycoprotein - CORRECT ANSWER -Protein with attached carbohydrate chains
Oligosaccharide - CORRECT ANSWER -Short carbohydrate chain attached to proteins or lipids
Proteoglycan - CORRECT ANSWER -Large carbohydrate-protein complex in the extracellular matrix
Lectin - CORRECT ANSWER -Carbohydrate-binding receptor protein involved in immune cell recognition
ACTUAL Questions and CORRECT Answers
Functional plasma membrane - CORRECT ANSWER -A membrane in mammals that creates a barrier between
internal and external environments, controls transport, receives signals, and remains flexible for movement and growth
Endomembrane system - CORRECT ANSWER -A network of connected lipid bilayer membranes inside
eukaryotic cells including the ER, Golgi, lysosomes, nucleus, and peroxisomes
Compartmentalization - CORRECT ANSWER -The division of the cell into specialized membrane-bound regions
with distinct functions
Smooth endoplasmic reticulum (smooth ER) - CORRECT ANSWER -Organelle where phospholipids are
synthesized for cellular membranes
Vesicle budding - CORRECT ANSWER -The process where a membrane pinches off to form a transport vesicle
Vesicle fusion - CORRECT ANSWER -The merging of a vesicle membrane with another membrane to deliver
contents
Phospholipid bilayer - CORRECT ANSWER -Double layer of phospholipids forming the basic structure of cell
membranes
Phospholipid - CORRECT ANSWER -Amphipathic lipid containing a hydrophilic head and hydrophobic fatty acid
tails
Hydrophilic - CORRECT ANSWER -Water-attracting or polar
Hydrophobic - CORRECT ANSWER -Water-repelling or nonpolar
Phosphatidylcholine - CORRECT ANSWER -Most common phospholipid found in mammalian cell membranes
Amphipathic - CORRECT ANSWER -Having both hydrophilic and hydrophobic regions
Cholesterol - CORRECT ANSWER -Membrane lipid that stabilizes membrane fluidity at extreme temperatures
Glycolipid - CORRECT ANSWER -Lipid with attached carbohydrate important for cell recognition and immune
response
Membrane fluidity - CORRECT ANSWER -The ability of lipids and proteins in a membrane to move within the
bilayer
Lateral diffusion - CORRECT ANSWER -Movement of lipids or proteins side-to-side within a membrane layer
Flip-flop movement - CORRECT ANSWER -Movement of lipids from one monolayer of the membrane to the
other
Scramblase - CORRECT ANSWER -ER enzyme that randomly transfers phospholipids between monolayers to
maintain balanced growth
Flippase - CORRECT ANSWER -Golgi enzyme that selectively transfers specific phospholipids between
membrane layers
Membrane asymmetry - CORRECT ANSWER -Unequal distribution of lipids and proteins between the two sides
of a membrane
Cytosolic side - CORRECT ANSWER -The membrane surface facing the cytoplasm
, Non-cytosolic side - CORRECT ANSWER -The membrane surface facing away from the cytoplasm or toward
organelle interiors/extracellular space
Membrane polarity - CORRECT ANSWER -The maintenance of distinct cytosolic and non-cytosolic membrane
orientations during vesicle transport
Membrane protein - CORRECT ANSWER -Protein associated with or embedded in the lipid bilayer
Transport protein - CORRECT ANSWER -Membrane protein that moves substances across the membrane
Channel protein - CORRECT ANSWER -Transport protein forming a pore that allows substances to move down
their electrochemical gradient
Transporter - CORRECT ANSWER -Protein that changes shape to move cargo across a membrane
Transmembrane protein - CORRECT ANSWER -Protein that spans the entire lipid bilayer
Monolayer-associated protein - CORRECT ANSWER -Protein embedded in only one membrane layer
Lipid-linked protein - CORRECT ANSWER -Protein covalently attached to a lipid in the membrane
Protein-attached protein - CORRECT ANSWER -Protein indirectly attached to the membrane through another
membrane protein
Alpha helix - CORRECT ANSWER -Common protein secondary structure stabilized by hydrogen bonds
Hydrophobic alpha helix - CORRECT ANSWER -Alpha helix with nonpolar side chains that can interact with the
membrane interior
Hydrophilic channel - CORRECT ANSWER -Passage formed by membrane proteins allowing polar molecules to
cross membranes
Cell cortex - CORRECT ANSWER -Meshwork of proteins attached to the cytosolic side of the plasma membrane
that supports cell shape
Extracellular matrix (ECM) - CORRECT ANSWER -Network of proteins and carbohydrates outside the cell
providing support and signaling
Diffusion barrier - CORRECT ANSWER -Structure such as a tight junction that restricts movement of membrane
proteins and lipids
Tight junction - CORRECT ANSWER -Cell junction that prevents diffusion of membrane components between
regions
Apical surface - CORRECT ANSWER -Top region of an epithelial cell facing outward or toward a lumen
Basal surface - CORRECT ANSWER -Bottom region of an epithelial cell attached to underlying tissue
Glycoprotein - CORRECT ANSWER -Protein with attached carbohydrate chains
Oligosaccharide - CORRECT ANSWER -Short carbohydrate chain attached to proteins or lipids
Proteoglycan - CORRECT ANSWER -Large carbohydrate-protein complex in the extracellular matrix
Lectin - CORRECT ANSWER -Carbohydrate-binding receptor protein involved in immune cell recognition
