Unlock hundreds more features
Save your Quiz to the Dashboard
View and Export Results
Use AI to Create Quizzes and Analyse Results

OR
Sign inSign in with Facebook
Sign inSign in with Google
Quizzes > Science > Biology

Identify Molecules Interacting with Cell Membrane Proteins - Take the Quiz

Ready to test your membrane transport and osmosis know-how?

Difficulty: Moderate
2-5mins
Learning OutcomesCheat Sheet
Paper art illustration for cell membrane proteins quiz on a coral background

Curious about how substances journey across the lipid bilayer? Our free scored quiz invites you to correctly identify these molecules that interact with cell membrane proteins , testing your grasp of diffusion, osmosis, and membrane trafficking quiz basics. From cell membrane structure quiz fundamentals to real-world membrane transport quiz scenarios, you'll spot channels, carriers, and pumps with confidence. Plus, try diffusion osmosis quiz questions to see how water and solutes navigate membranes. Ready to challenge yourself? Jump in and prove your skills today!

Which small nonpolar gas molecule freely diffuses across the lipid bilayer?
Oxygen
Glucose
Sodium ion
Sucrose
Oxygen is a small nonpolar molecule that can diffuse directly through the hydrophobic core of the lipid bilayer without assistance. Polar or charged molecules like glucose and sodium ions require transporters or channels. Sucrose is too large and polar to cross without facilitation. More on diffusion
What process describes the movement of water across a semipermeable membrane in response to solute concentration?
Osmosis
Simple diffusion
Active transport
Facilitated diffusion
Osmosis is the passive movement of water through a semipermeable membrane down its concentration gradient. It does not require energy or carrier proteins. Simple diffusion refers to solute movement, while active transport requires ATP. Read about osmosis
Which transport protein lowers the activation energy for solute passage without using ATP?
Carrier protein
Na?/K? ATPase
Ligand-gated channel
Vesicle transporter
Carrier proteins facilitate the movement of specific molecules across the membrane by undergoing conformational changes, lowering the activation energy for transport without ATP. Na?/K? ATPase uses ATP directly. Ligand-gated channels open in response to ligand binding but do not actively change their activation energy. Details on carrier proteins
Which molecule cannot cross the cell membrane by simple diffusion?
Glucose
Carbon dioxide
Oxygen
Ethanol
Glucose is a large polar molecule that cannot diffuse through the hydrophobic core of the membrane; it requires specific transporters. Small nonpolar molecules like CO?, O?, and ethanol diffuse readily. Cell membrane permeability
Which direction does the Na?/K? ATPase pump move sodium ions relative to the cell?
Out of the cell
Into the cell
Equally in and out
No net movement
The Na?/K? ATPase actively transports three sodium ions out of the cell and two potassium ions in per ATP hydrolyzed, maintaining the electrochemical gradients. This is primary active transport. Na?/K? pump function
What type of transport requires ATP directly to move molecules against their concentration gradient?
Primary active transport
Facilitated diffusion
Simple diffusion
Osmosis
Primary active transport uses ATP hydrolysis to move molecules against their concentration gradient, as seen in pumps like Na?/K? ATPase. Facilitated diffusion and simple diffusion do not use energy, and osmosis refers to water movement. Active transport overview
Which transporter is responsible for facilitated diffusion of glucose into most mammalian cells?
GLUT1
Aquaporin-1
Na? voltage-gated channel
ATP synthase
GLUT1 is a facilitative glucose transporter widely expressed in mammalian cells, allowing glucose to move down its concentration gradient. Aquaporins transport water, voltage-gated channels handle ions, and ATP synthase makes ATP. About GLUT1
What is the primary lipid component of the eukaryotic plasma membrane?
Phospholipids
Cholesterol
Glycoproteins
Glycolipids
Phospholipids form a bilayer that is the fundamental structure of the plasma membrane, with hydrophilic heads and hydrophobic tails. Cholesterol modulates fluidity but is not the main structural lipid. Glycoproteins and glycolipids are membrane components but in smaller amounts. Phospholipid bilayer
Which type of membrane protein associates loosely and can be removed without disrupting the bilayer?
Peripheral membrane protein
Integral membrane protein
Transmembrane protein
Lipid-anchored protein
Peripheral membrane proteins bind to the membrane surface or to integral proteins via noncovalent interactions and can be removed with mild treatments. Integral and transmembrane proteins span or embed in the bilayer. Lipid-anchored proteins are covalently attached to lipid molecules. Peripheral proteins
What do aquaporins specifically facilitate across the membrane?
Water
Glucose
Chloride ions
Amino acids
Aquaporins are channel proteins that selectively allow water molecules to traverse the membrane rapidly while excluding ions and other solutes. This specificity is critical for regulating water balance. Aquaporin function
Which ion channel opens in response to changes in membrane potential?
Voltage-gated Na? channel
Ligand-gated Cl? channel
Mechanosensitive K? channel
Gap junction channel
Voltage-gated Na? channels respond to depolarization of the membrane, opening to allow Na? influx. Ligand-gated channels open in response to ligand binding, mechanosensitive channels respond to stretch, and gap junctions connect cells directly. Voltage-gated channels
What term describes the property of the plasma membrane that allows some substances to pass but not others?
Selective permeability
Permeability barrier
Fluid mosaic
Isotonicity
Selective permeability refers to the membrane's ability to allow certain molecules or ions to pass while restricting others, critical for homeostasis. The fluid mosaic model describes membrane structure but not permeability itself. Selective permeability
Which receptor type spans the membrane seven times and interacts with G-proteins?
G-protein coupled receptor (GPCR)
Receptor tyrosine kinase
Ionotropic receptor
Intracellular nuclear receptor
GPCRs have seven transmembrane ?-helices and activate intracellular G-proteins upon ligand binding. Receptor tyrosine kinases have a single helix, ionotropic receptors form channels, and nuclear receptors are intracellular. About GPCRs
Which membrane component increases fluidity at low temperatures?
Cholesterol
Saturated fatty acids
Glycoproteins
Transmembrane domains
Cholesterol disrupts close packing of phospholipid tails at low temperatures, preventing rigidity and maintaining fluidity. Saturated fatty acids pack tightly and reduce fluidity. Cholesterol in membranes
Which endocytic process involves uptake of small volumes of extracellular fluid and solutes?
Pinocytosis
Phagocytosis
Receptor-mediated endocytosis
Exocytosis
Pinocytosis nonspecifically engulfs small amounts of extracellular fluid and solutes in vesicles. Phagocytosis involves large particles, receptor-mediated endocytosis is cargo-specific, and exocytosis exports materials. Pinocytosis details
Which amino acid residues are most likely found within the transmembrane helices of an integral protein?
Hydrophobic residues (e.g., leucine, isoleucine)
Polar uncharged residues (e.g., serine, threonine)
Positively charged residues (e.g., lysine, arginine)
Negatively charged residues (e.g., aspartate, glutamate)
Transmembrane ?-helices span the hydrophobic core of the lipid bilayer and are rich in hydrophobic amino acids like leucine and isoleucine. Polar and charged residues are energetically unfavorable in that environment. Transmembrane protein structure
Which carrier-mediated transport exhibits saturation kinetics as substrate concentration increases?
Facilitated diffusion of glucose
Simple diffusion of O?
Osmosis of water
Passive diffusion of ethanol
Carrier proteins involved in facilitated diffusion have a finite number of binding sites, leading to saturation kinetics (Tm) at high substrate concentrations. Simple diffusion processes do not saturate. Facilitated diffusion kinetics
Which type of ion channel opens in response to a specific ligand binding extracellularly?
Ligand-gated channel
Voltage-gated channel
Mechanosensitive channel
Aquaporin
Ligand-gated channels open upon binding of a specific ligand (e.g., neurotransmitters) to extracellular sites. Voltage-gated channels respond to membrane potential changes, mechanosensitive channels to physical forces, and aquaporins transport water. Ligand-gated channels
Which process couples the inward movement of glucose with sodium down its gradient?
Secondary active transport
Primary active transport
Simple diffusion
Facilitated diffusion
Secondary active transport uses the energy of one molecules electrochemical gradient (e.g., Na?) to drive the uphill transport of another (e.g., glucose). Primary active transport uses ATP directly. Facilitated diffusion is energy-independent. Secondary active transport
Which lipid modification anchors some proteins to the cytosolic face of the membrane?
Prenylation
Glycosylation
Phosphorylation
Ubiquitination
Prenylation attaches hydrophobic isoprene groups to proteins, anchoring them to the membranes cytosolic side. Glycosylation occurs in the lumen or extracellular face. Phosphorylation and ubiquitination are regulatory modifications. Protein prenylation
Which method measures the movement of a radiolabeled ligand into vesicles to study transporter function?
Uptake assay
Patch-clamp recording
Western blot
Mass spectrometry
Uptake assays track radioisotope-labeled substrates moving into vesicles or cells to quantify transport activity. Patch-clamp measures currents, Western blot detects proteins, and mass spectrometry analyzes mass-to-charge ratios. Uptake assays
Which domain of a receptor tyrosine kinase binds ATP and transfers phosphate groups?
Kinase domain
Ligand-binding domain
Transmembrane domain
Juxtamembrane domain
The kinase domain of receptor tyrosine kinases catalyzes the transfer of a phosphate group from ATP to tyrosine residues on substrate proteins. The ligand-binding domain interacts with the growth factor, and the transmembrane domain spans the membrane. Receptor tyrosine kinases
In clathrin-mediated endocytosis, what protein triskelions assemble to form?
Coated vesicle cage
Dynamin collar
Adaptor complex
SNARE complex
Clathrin triskelions assemble into a polyhedral cage around a budding vesicle, stabilizing its shape before scission. Dynamin pinches off the vesicle, adaptors link cargo to clathrin, and SNAREs mediate fusion. Clathrin-mediated endocytosis
Which gradient provides the driving force for the Na?/glucose symporter in the intestinal epithelium?
Na? electrochemical gradient
Glucose concentration gradient
ATP concentration gradient
Proton gradient
The Na?/glucose symporter uses the inward Na? electrochemical gradient established by Na?/K? ATPase to drive glucose uptake against its concentration gradient. Glucose gradient alone is insufficient, and neither ATP nor protons are directly used. Na?/glucose cotransporter
Which assay uses fluorescent tags to measure real-time ion channel activity?
Patch-clamp fluorimetry
ELISA
FACS
Southern blot
Patch-clamp fluorimetry combines patch-clamp electrophysiology with fluorescent indicators to monitor ion flux in real time. ELISA measures proteins, FACS analyzes cells, and Southern blot detects DNA. Patch-clamp method
Which structural motif often forms water-filled pores in channel proteins?
Beta-barrel
Coiled-coil
Leucine zipper
Zinc finger
Beta-barrel motifs in transmembrane proteins create cylindrical channels permitting solute passage, as seen in bacterial porins. Coiled-coils, leucine zippers, and zinc fingers are proteinprotein or DNA-binding motifs. Beta-barrel structures
Which membrane property depends on the length and saturation of fatty acid chains?
Fluidity
Charge
Permeability only to ions
Thickness of cell wall
Membrane fluidity increases with shorter and more unsaturated fatty acid chains due to reduced van der Waals interactions. Chain length and saturation do not determine membrane charge or cell wall thickness. Membrane fluidity
Which technique can determine the orientation of transmembrane helices?
Hydropathy plot analysis
Southern blotting
Mass spectrometry
qPCR
Hydropathy plots analyze amino acid hydrophobicity along a sequence to predict transmembrane helices and their orientation. Southern blotting detects DNA, mass spectrometry analyzes mass, and qPCR quantifies nucleic acids. Hydropathy plots
Which lipid raft component concentrates certain proteins for signaling?
Sphingolipids
Phosphatidylinositol
Phosphatidylcholine
Cardiolipin
Sphingolipids and cholesterol cluster in membrane microdomains called lipid rafts, organizing signaling proteins. Phosphatidylinositol and phosphatidylcholine are common phospholipids not specifically raft-associated. Lipid rafts
Which parameter in Michaelis-Menten kinetics indicates the transporters affinity for its substrate?
Km
Vmax
kcat
IC50
Km, the Michaelis constant, reflects the substrate concentration at which transport rate is half-maximal, indicating transporter affinity. A low Km means high affinity. Vmax is maximal rate, kcat is turnover number, and IC50 is inhibitor potency. Michaelis-Menten
Which technique would you use to resolve the 3D structure of a membrane protein at atomic resolution?
Cryo-electron microscopy
Flow cytometry
Northern blot
Surface plasmon resonance
Cryo-EM allows visualization of membrane proteins in near-native conditions at atomic resolution. Flow cytometry analyzes cell populations, Northern blots RNA, and SPR measures binding kinetics. Cryo-EM
Which mutation in a channel protein pore would most likely alter ion selectivity?
Substitution of a negatively charged residue lining the pore
Deletion of C-terminal tail
Replacement of a glycosylation site
Mutation in extracellular loop far from pore
Ion selectivity of channels is determined by the charged residues lining the selectivity filter; changing a negative residue to neutral or positive will alter selectivity. Other mutations outside the pore region have lesser effects on ion discrimination. Ion channel structure
Which transporter is inhibited by ouabain, affecting cardiac myocyte ion balance?
Na?/K? ATPase
Ca? ATPase
GLUT4
Na?/glucose symporter
Ouabain binds to and inhibits the Na?/K? ATPase, raising intracellular Na?, which indirectly increases intracellular Ca? via the Na?/Ca? exchanger, impacting cardiac contractility. Other transporters are unaffected. Ouabain effect
Which experimental method measures the free energy change of receptor-ligand binding?
Isothermal titration calorimetry
Western blot
Patch-clamp recording
Fluorescent microscopy
Isothermal titration calorimetry directly measures heat released or absorbed during binding, allowing calculation of ?G, ?H, and ?S. Western blots detect proteins, patch-clamp measures currents, and fluorescence microscopy visualizes molecules. ITC method
Which domain of membrane receptors often interacts with intracellular signaling partners?
Cytoplasmic tail
Extracellular N-terminus
Transmembrane helix
Signal peptide
The cytoplasmic tail of transmembrane receptors contains motifs for interaction with intracellular signaling proteins and effectors. The extracellular N-terminus binds ligands, transmembrane helices span the bilayer, and signal peptides direct insertion. Signal transduction
Which analytical technique can quantify membrane proteinligand binding kinetics in real time without labels?
Surface plasmon resonance
ELISA
Western blot
Immunofluorescence
Surface plasmon resonance measures changes in refractive index upon ligand binding to immobilized protein, providing real-time on/off rates without labeling. ELISA and Western blots require antibodies, and immunofluorescence uses labels. SPR overview
Which mutation in the ATP-binding site of a P-type ATPase would abolish transport activity?
Lysine to alanine in Walker A motif
Serine to threonine in a peripheral loop
Glycosylation site mutation in extracellular loop
Hydrophobic residue change in transmembrane helix 7
The lysine in the Walker A motif is critical for binding the phosphate groups of ATP; its substitution abolishes ATP hydrolysis and transport. Other mutations outside the catalytic site have lesser effects on ATP binding. Walker A motif
Which intracellular organelle uses membrane channels to release Ca? into the cytosol during signaling?
Endoplasmic reticulum
Golgi apparatus
Mitochondria
Lysosome
The endoplasmic reticulum stores Ca? and releases it via IP? or ryanodine receptor channels during signaling events. Mitochondria can buffer calcium but are not primary stores, and Golgi and lysosomes handle other functions. ER calcium handling
Which advanced method can isolate native membrane proteins in lipid nanodiscs for study?
Styrenemaleic acid copolymer extraction
Detergent micelle solubilization
Guanidine hydrochloride extraction
Ethanol precipitation
Styrenemaleic acid copolymers can solubilize membrane proteins directly into nanodiscs, preserving the native lipid environment without detergents. Traditional detergent solubilization can disrupt lipidprotein interactions. Lipid nanodiscs
Which electrophysiological signature indicates channel inactivation after opening?
Transient current that decays despite maintained stimulus
Sustained plateau current
Delayed permanent closure
No initial current
Inactivation is characterized by a rapid decay of current after channel opening even though the activating stimulus persists. A sustained plateau indicates non-inactivating channels. Channel inactivation
Which protein motif binds to PIP2 lipids to recruit cytoskeletal elements to the membrane?
PH domain
SH2 domain
Zinc finger
Homeobox
Pleckstrin homology (PH) domains specifically bind phosphatidylinositol 4,5-bisphosphate (PIP?) in the membrane, aiding recruitment of proteins involved in cytoskeletal regulation. SH2 domains bind phosphotyrosine, zinc fingers bind DNA, and homeoboxes are transcription factors. PH domain
Which computational approach predicts membrane protein folding within a lipid environment?
Molecular dynamics in explicit bilayer
Homology modeling in water
Docking with water-only solvent
Quantum mechanics of isolated peptide
Simulating molecular dynamics with an explicit lipid bilayer environment best captures membrane protein folding and interactions. Homology modeling and water-only solvents ignore the lipid context, and quantum methods are computationally limited for large proteins. Molecular dynamics
Which advanced mass spectrometry technique maps proteinlipid interaction sites on membrane proteins?
Hydrogendeuterium exchange MS
MALDI-TOF
GC-MS
ICP-MS
Hydrogendeuterium exchange coupled to mass spectrometry reveals solvent-accessible regions and lipid-binding sites by measuring exchange rates. MALDI-TOF is general protein analysis, GC-MS for volatile compounds, and ICP-MS for metal ions. HDX-MS
Which concept describes how membrane protein crowding affects lateral diffusion?
Percolation threshold
Goldilocks effect
Bohr effect
Hill coefficient
The percolation threshold refers to the critical density of obstacles (e.g., proteins) beyond which lateral diffusion becomes constrained. The other terms describe unrelated phenomena in biochemistry. Percolation theory
Which technique can resolve single-molecule interactions of membrane proteins in live cells using zero-mode waveguides?
Single-molecule fluorescence spectroscopy
Fluorescence recovery after photobleaching
Total internal reflection fluorescence
Two-photon microscopy
Zero-mode waveguides allow single-molecule fluorescence detection in live-cell membranes at high concentrations, revealing individual binding events. FRAP measures ensemble recovery, TIRF and two-photon have other spatial/light limitations. Zero-mode waveguides
Which biophysical principle explains how membrane tension influences mechanosensitive channel gating?
Energy landscape shift due to bilayer deformation
Electrostatic repulsion increase
Ligand binding affinity change
ATP hydrolysis rate
Membrane tension deforms the lipid bilayer, altering the energetic barrier for mechanosensitive channel conformational changes, effectively shifting the gating energy landscape. This is not primarily due to electrostatics, ligand affinity, or ATP. Mechanosensitive channels
0
{"name":"Which small nonpolar gas molecule freely diffuses across the lipid bilayer?", "url":"https://www.quiz-maker.com/QPREVIEW","txt":"Which small nonpolar gas molecule freely diffuses across the lipid bilayer?, What process describes the movement of water across a semipermeable membrane in response to solute concentration?, Which transport protein lowers the activation energy for solute passage without using ATP?","img":"https://www.quiz-maker.com/3012/images/ogquiz.png"}

Study Outcomes

  1. Understand Membrane Architecture -

    Explain the key components of cell membrane structure and how lipids, proteins, and carbohydrates assemble to form the fluid mosaic.

  2. Identify Interacting Molecules -

    Correctly identify these molecules that interact with cell membrane proteins by recognizing ligands, ions, and substrates involved in membrane dynamics.

  3. Apply Diffusion and Osmosis Concepts -

    Use principles from the diffusion osmosis quiz to predict solute movement across membranes under different concentration gradients.

  4. Differentiate Transport Mechanisms -

    Distinguish between passive, facilitated, and active transport in the context of the membrane transport quiz scenarios.

  5. Analyze Membrane Trafficking Pathways -

    Evaluate endocytosis, exocytosis, and vesicle-mediated transport steps, as presented in the membrane trafficking quiz.

  6. Interpret Quiz Feedback -

    Leverage scored results to pinpoint areas for review and reinforce understanding of cell membrane structure quiz topics.

Cheat Sheet

  1. Ion Channels and Electrochemical Gradients -

    Ion channels selectively conduct Na❺, K❺, Ca²❺, or Cl❻ based on pore size and charge, and the Nernst equation (E = (RT/zF)·ln([out]/[in])) predicts each ion's equilibrium potential. Use the mnemonic "NAKED" (Na❺ Anions K❺ Equilibrium Deduced) to recall which ions follow the electrochemical gradient. Mastering this concept is critical for any membrane transport quiz or cell membrane structure quiz.

  2. Facilitated Diffusion via Carrier Proteins -

    Carrier proteins like GLUT1 shuttle glucose down its concentration gradient without ATP, demonstrating Michaelis - Menten kinetics (V = Vmax[S]/(Km+[S])). Remember "GLUT GO!" to link GLUT transporters and glucose uptake in red blood cells. This applies directly when you correctly identify these molecules that interact with cell membrane proteins on a diffusion osmosis quiz.

  3. Aquaporins and Osmosis Control -

    Aquaporin channels accelerate water flux by over 10❹ molecules per second, maintaining osmotic balance; water moves from low to high solute concentration regions. Mnemonic "Aqua Pores = Pure H₂O Passage" can help you recall their selective permeability. Questions about osmosis often feature aquaporins in both cell membrane structure quizzes and diffusion osmosis quizzes.

  4. Receptor - Ligand Specificity -

    Membrane receptors (e.g., GPCRs, tyrosine kinases) bind hormones like insulin or epinephrine via the lock-and-key model, triggering second messenger cascades (cAMP, IP₃). Use "RACK" (Receptor Affinity Controls Kinase) to remember kinase-linked receptors. A solid grasp here powers your success on any membrane transport quiz or membrane trafficking quiz when identifying signaling molecules.

  5. Vesicular Trafficking and SNAREs -

    Clathrin-coated vesicles and SNARE proteins mediate endocytosis and exocytosis, guiding cargo like LDL or neurotransmitters to their destinations. Think "v-SNAREs vouch for vesicle fusion" to recall function. This pathway is often tested in membrane trafficking quizzes and reinforces how to correctly identify these molecules that interact with cell membrane proteins.

Make a Quiz (FREE) Copy & Edit This Quiz Create a Quiz with AI

Biology Quizzes

Powered by: Quiz Maker