High school / pre-med / IB-style questions on membrane receptor types (GPCRs, ion channels, RTKs, intracellular receptors) with a focus on GPCR logic: why cells need membrane receptors, why cascades and amplification exist, second messengers (cAMP, IP3/DAG, Ca2+), and how signals are turned off (desensitization, GTP hydrolysis, PDE).
A peptide hormone is released into the blood and reaches many tissues, but only some tissues respond. What is the MOST direct reason a peptide hormone typically needs a membrane receptor to affect a cell?
Source: entermedschool.org
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src="https://entermedschool.org/embed/questions#{"title":"Membrane Receptors & GPCR Signaling","questions":[{"prompt":"A peptide hormone is released into the blood and reaches many tissues, but only some tissues respond. What is the MOST direct reason a peptide hormone typically needs a membrane receptor to affect a cell?","options":[{"label":"A","body":"Peptide hormones are too large to exist in blood without receptors.","isCorrect":false},{"label":"B","body":"Peptide hormones are usually polar, so they cannot freely diffuse through the lipid bilayer to reach intracellular targets.","isCorrect":true},{"label":"C","body":"Peptide hormones must be converted into ATP before a cell can respond.","isCorrect":false},{"label":"D","body":"Peptide hormones can only act on cells that have mitochondria.","isCorrect":false},{"label":"E","body":"Peptide hormones only work by binding directly to DNA in the nucleus.","isCorrect":false}],"explanation":"Most peptide hormones are hydrophilic, so they can’t cross the hydrophobic membrane core. A membrane receptor allows an external signal (first messenger) to be converted into an internal response. Blood transport and mitochondria are not the limiting issue here."},{"prompt":"Which signaling molecule is MOST likely to act through a G‑protein‑coupled receptor (GPCR) on the cell surface?","options":[{"label":"A","body":"Cortisol (a steroid hormone)","isCorrect":false},{"label":"B","body":"Thyroid hormone (lipid-soluble)","isCorrect":false},{"label":"C","body":"Adrenaline/epinephrine (a catecholamine)","isCorrect":true},{"label":"D","body":"Nitric oxide (a gas)","isCorrect":false},{"label":"E","body":"Oxygen","isCorrect":false}],"explanation":"Catecholamines like adrenaline are water-soluble and typically signal via cell-surface receptors such as GPCRs. Steroids and thyroid hormone usually act via intracellular receptors, and gases like NO diffuse across membranes without needing a surface receptor."},{"prompt":"A student says: “If a hormone binds a receptor, the hormone must enter the cell.” Which statement is the best correction?","options":[{"label":"A","body":"Correct—binding always requires the hormone to pass through the membrane first.","isCorrect":false},{"label":"B","body":"Incorrect—many hormones bind membrane receptors and trigger intracellular signaling without entering the cell.","isCorrect":true},{"label":"C","body":"Incorrect—hormones never bind receptors; they bind enzymes.","isCorrect":false},{"label":"D","body":"Correct—only steroid hormones can bind receptors.","isCorrect":false},{"label":"E","body":"Incorrect—hormones act only by changing membrane cholesterol content.","isCorrect":false}],"explanation":"Many signals (especially hydrophilic ones) bind to cell-surface receptors, which then start intracellular cascades. Only some hormones (like many steroids) cross the membrane to bind intracellular receptors."},{"prompt":"Which structural feature is most characteristic of GPCRs?","options":[{"label":"A","body":"A single transmembrane helix and a ligand-binding domain inside the nucleus","isCorrect":false},{"label":"B","body":"Seven transmembrane segments (typically alpha-helices)","isCorrect":true},{"label":"C","body":"A pore that directly conducts Na+ and K+ ions when the ligand binds","isCorrect":false},{"label":"D","body":"A cytosolic catalytic domain that phosphorylates tyrosine residues by itself","isCorrect":false},{"label":"E","body":"Two lipid bilayers surrounding the receptor protein","isCorrect":false}],"explanation":"GPCRs are famous for their 7-transmembrane structure. Ion channels form pores; receptor tyrosine kinases have intrinsic kinase activity; none of those define GPCRs."},{"prompt":"A heterotrimeric G protein is best described as:","options":[{"label":"A","body":"A DNA-binding protein made of three chromosomes","isCorrect":false},{"label":"B","body":"A three-subunit protein (α, β, γ) that binds GDP/GTP and relays signals from GPCRs","isCorrect":true},{"label":"C","body":"A membrane lipid made of three fatty acids","isCorrect":false},{"label":"D","body":"A receptor that directly phosphorylates glucose","isCorrect":false},{"label":"E","body":"An ion channel with three gates","isCorrect":false}],"explanation":"The “G” refers to guanine nucleotides (GDP/GTP). Heterotrimeric G proteins have α, β, and γ subunits and transmit signals from GPCRs to effector proteins."},{"prompt":"In the classic GPCR cycle, which event MOST directly switches the Gα subunit into its active state?","options":[{"label":"A","body":"Phosphorylation of Gα by the receptor","isCorrect":false},{"label":"B","body":"Exchange of GDP for GTP on Gα","isCorrect":true},{"label":"C","body":"Hydrolysis of ATP to ADP on Gα","isCorrect":false},{"label":"D","body":"Binding of oxygen to Gα","isCorrect":false},{"label":"E","body":"Removal of the membrane lipids around the receptor","isCorrect":false}],"explanation":"Activated GPCRs act like a ‘GEF’ for Gα, promoting GDP release and GTP binding. It’s the GDP→GTP swap (not receptor phosphorylation) that activates Gα."},{"prompt":"A student says: “GPCRs amplify signals because one hormone molecule can enter and directly activate thousands of enzymes.” What is the best correction?","options":[{"label":"A","body":"Correct—hormones enter cells and directly activate thousands of enzymes by themselves.","isCorrect":false},{"label":"B","body":"Incorrect—amplification usually occurs because one activated receptor can activate many G proteins, each triggering downstream enzyme activity and second messengers.","isCorrect":true},{"label":"C","body":"Incorrect—amplification is impossible in biology; responses are always one-to-one.","isCorrect":false},{"label":"D","body":"Correct—amplification is caused mainly by increased diffusion speed of hormones.","isCorrect":false},{"label":"E","body":"Incorrect—GPCRs are channels, so no cascades are involved.","isCorrect":false}],"explanation":"Amplification is a property of cascades: one receptor can activate multiple G proteins; each can activate an effector enzyme; each enzyme can generate many second messenger molecules. The hormone typically does not need to enter the cell."},{"prompt":"Why do cells often use multi-step signaling cascades instead of a single-step “receptor → final response” system?","options":[{"label":"A","body":"Cascades always make responses slower and less controllable, which cells prefer.","isCorrect":false},{"label":"B","body":"Cascades allow amplification and also provide multiple control points for regulation and integration of signals.","isCorrect":true},{"label":"C","body":"Cascades are needed because receptors cannot bind ligands tightly.","isCorrect":false},{"label":"D","body":"Cascades are used only in plants, not animals.","isCorrect":false},{"label":"E","body":"Cascades prevent the need for ATP in signaling.","isCorrect":false}],"explanation":"Cascades do more than amplify: they create checkpoints, allow branching, integrate multiple inputs, and shape timing. Slower speed can be a tradeoff, not the goal."},{"prompt":"A key trade-off of using signaling cascades (like GPCR → second messengers → kinases) is that cascades:","options":[{"label":"A","body":"Prevent signal amplification","isCorrect":false},{"label":"B","body":"Can be slower than direct ion channel signaling, but allow amplification and fine-tuned regulation","isCorrect":true},{"label":"C","body":"Require the ligand to enter the nucleus","isCorrect":false},{"label":"D","body":"Always produce identical responses in every tissue","isCorrect":false},{"label":"E","body":"Work only in bacteria","isCorrect":false}],"explanation":"Ligand-gated ion channels can change membrane potential in milliseconds. GPCR cascades are often slower (seconds) but provide amplification, regulation, and signal integration."},{"prompt":"Which receptor type is most likely to produce the FASTEST response after ligand binding?","options":[{"label":"A","body":"Intracellular nuclear receptor","isCorrect":false},{"label":"B","body":"Receptor tyrosine kinase (RTK)","isCorrect":false},{"label":"C","body":"Ligand-gated ion channel","isCorrect":true},{"label":"D","body":"GPCR signaling through a kinase cascade","isCorrect":false},{"label":"E","body":"A receptor that only changes gene transcription after hours","isCorrect":false}],"explanation":"Ligand-gated ion channels directly change ion flow, so they act fastest. GPCRs and RTKs usually act through multi-step signaling; nuclear receptors often change transcription and are slower."},{"prompt":"Acetylcholine can act through two receptor families: nicotinic and muscarinic. Which statement is correct?","options":[{"label":"A","body":"Nicotinic receptors are GPCRs; muscarinic receptors are ligand-gated ion channels.","isCorrect":false},{"label":"B","body":"Muscarinic receptors are GPCRs; nicotinic receptors are ligand-gated ion channels.","isCorrect":true},{"label":"C","body":"Both nicotinic and muscarinic receptors are intracellular receptors.","isCorrect":false},{"label":"D","body":"Both are receptor tyrosine kinases.","isCorrect":false},{"label":"E","body":"Neither receptor binds acetylcholine directly.","isCorrect":false}],"explanation":"Nicotinic ACh receptors are ion channels (fast). Muscarinic ACh receptors are GPCRs (often slower, modulatory)."},{"prompt":"Which statement best distinguishes an RTK (receptor tyrosine kinase) from a GPCR?","options":[{"label":"A","body":"RTKs have 7 transmembrane helices; GPCRs have one.","isCorrect":false},{"label":"B","body":"RTKs often dimerize and autophosphorylate tyrosine residues; GPCRs signal mainly by activating heterotrimeric G proteins.","isCorrect":true},{"label":"C","body":"RTKs are always ion channels; GPCRs are always enzymes.","isCorrect":false},{"label":"D","body":"GPCRs can only respond to steroid hormones; RTKs respond only to light.","isCorrect":false},{"label":"E","body":"GPCRs work only in bacteria; RTKs work only in plants.","isCorrect":false}],"explanation":"RTKs are typically single-pass receptors that activate kinase signaling via tyrosine phosphorylation (often after dimerization). GPCRs are 7-pass receptors that activate G proteins and second messengers."},{"prompt":"Insulin is best matched with which receptor type?","options":[{"label":"A","body":"Ligand-gated ion channel","isCorrect":false},{"label":"B","body":"GPCR (Gs)","isCorrect":false},{"label":"C","body":"Receptor tyrosine kinase (RTK)","isCorrect":true},{"label":"D","body":"Intracellular nuclear receptor","isCorrect":false},{"label":"E","body":"Voltage-gated sodium channel","isCorrect":false}],"explanation":"At this level, insulin is classically linked to an RTK pathway (phosphorylation cascades). GPCRs (Gs/Gi/Gq) are used by many other hormones and neurotransmitters, but not the classic insulin receptor."},{"prompt":"A hormone binds a GPCR and causes a rapid increase in intracellular cAMP. Which Gα type is the BEST match?","options":[{"label":"A","body":"Gαs","isCorrect":true},{"label":"B","body":"Gαi","isCorrect":false},{"label":"C","body":"Gαq","isCorrect":false},{"label":"D","body":"Tubulin","isCorrect":false},{"label":"E","body":"Actin","isCorrect":false}],"explanation":"Gαs stimulates adenylyl cyclase, increasing cAMP production. Gαi inhibits adenylyl cyclase, and Gαq activates phospholipase C (IP3/DAG pathway)."},{"prompt":"A GPCR activation leads to a DECREASE in cAMP levels. Which Gα type is the BEST match?","options":[{"label":"A","body":"Gαs","isCorrect":false},{"label":"B","body":"Gαi","isCorrect":true},{"label":"C","body":"Gαq","isCorrect":false},{"label":"D","body":"RNA polymerase","isCorrect":false},{"label":"E","body":"Myosin","isCorrect":false}],"explanation":"Gαi inhibits adenylyl cyclase, lowering cAMP. Gαs does the opposite, and Gαq mainly drives IP3/DAG and Ca2+ signaling."},{"prompt":"A signal activates a GPCR that increases intracellular Ca2+ by releasing Ca2+ from the endoplasmic reticulum. Which pathway is most consistent with this?","options":[{"label":"A","body":"Gαs → adenylyl cyclase → cAMP","isCorrect":false},{"label":"B","body":"Gαi → inhibition of adenylyl cyclase","isCorrect":false},{"label":"C","body":"Gαq → phospholipase C → IP3 + DAG","isCorrect":true},{"label":"D","body":"RTK → direct opening of Na+ channels","isCorrect":false},{"label":"E","body":"Steroid receptor → DNA binding → immediate Ca2+ release","isCorrect":false}],"explanation":"Gαq activates phospholipase C, producing IP3 and DAG. IP3 binds ER receptors and triggers Ca2+ release. cAMP (Gs) signaling is a different branch."},{"prompt":"Which statement about IP3 and DAG is correct?","options":[{"label":"A","body":"IP3 remains in the membrane and activates protein kinase C directly.","isCorrect":false},{"label":"B","body":"DAG diffuses through the cytosol to bind receptors on the ER.","isCorrect":false},{"label":"C","body":"IP3 diffuses in the cytosol and can trigger Ca2+ release from the ER; DAG stays in the membrane and helps activate protein kinase C.","isCorrect":true},{"label":"D","body":"Both IP3 and DAG are steroid hormones.","isCorrect":false},{"label":"E","body":"IP3 is a membrane channel; DAG is a nuclear transcription factor.","isCorrect":false}],"explanation":"IP3 is soluble and travels to the ER to open Ca2+ channels. DAG is hydrophobic and stays in the membrane, helping activate PKC (often together with Ca2+)."},{"prompt":"Which molecule is a classic SECOND messenger produced/used inside cells during signaling?","options":[{"label":"A","body":"Insulin (in the bloodstream)","isCorrect":false},{"label":"B","body":"cAMP","isCorrect":true},{"label":"C","body":"A GPCR protein","isCorrect":false},{"label":"D","body":"A hormone receptor gene","isCorrect":false},{"label":"E","body":"Hemoglobin","isCorrect":false}],"explanation":"Second messengers (like cAMP, Ca2+, IP3) are intracellular signaling molecules that spread/amplify the signal after receptor activation. Insulin is an extracellular first messenger in this context."},{"prompt":"Which option is NOT a second messenger in the typical GPCR sense?","options":[{"label":"A","body":"Ca2+","isCorrect":false},{"label":"B","body":"cAMP","isCorrect":false},{"label":"C","body":"IP3","isCorrect":false},{"label":"D","body":"DAG","isCorrect":false},{"label":"E","body":"Adrenaline/epinephrine (the extracellular signal)","isCorrect":true}],"explanation":"Adrenaline is a first messenger (outside the cell). cAMP, Ca2+, IP3 and DAG act inside the cell to relay/amplify the signal."},{"prompt":"A drug inhibits phosphodiesterase (PDE), the enzyme that breaks down cAMP. In a cell using a cAMP pathway, the MOST likely result is:","options":[{"label":"A","body":"cAMP signals become weaker and shorter","isCorrect":false},{"label":"B","body":"cAMP signals become stronger and/or last longer","isCorrect":true},{"label":"C","body":"cAMP can no longer be produced by adenylyl cyclase","isCorrect":false},{"label":"D","body":"The GPCR is converted into an ion channel","isCorrect":false},{"label":"E","body":"The hormone must now enter the nucleus to work","isCorrect":false}],"explanation":"If breakdown is blocked, cAMP accumulates and persists, so downstream signaling tends to be stronger/longer. Production is still controlled by adenylyl cyclase upstream."}]}"
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