GPAT 2026 Question Paper with Answer Key & Explanations (Memory-Based)
GPAT 2026 memory-based questions are highly useful for understanding the latest exam trend, high-yield topics, and subject-wise focus areas. Based on student recall, we have compiled these questions with answers and concise explanations to help aspirants revise smarter.
This subject-wise GPAT 2026 memory-based answer key covers Pharmacology, HAP, Pharmaceutical Chemistry, Analysis, Pharmaceutics, Pharmacognosy, Microbiology, Biotechnology, and Jurisprudence in one place.
Pharmacology & Human Anatomy and Physiology (HAP)
Typical Antipsychotic: What is the mechanism of action of Haloperidol?
Answer: D2 receptor antagonist.
Explanation: Haloperidol is a typical antipsychotic that mainly blocks dopamine D2 receptors in the brain, especially in the mesolimbic pathway. This reduces positive symptoms of psychosis such as hallucinations and delusions.
Orphan Drugs: What are orphan drugs used for?
Answer: Rare diseases.
Explanation: Orphan drugs are developed for the treatment, prevention, or diagnosis of rare diseases that affect a small population. These conditions often receive special regulatory support because they are less commercially attractive.
Cyproheptadine Mechanism: What is the pharmacological action of Cyproheptadine?
Answer: It is an antihistaminic and an antiserotonergic (5-HT2A receptor antagonist) used as an appetite stimulant.
Explanation: Cyproheptadine blocks H1 histamine receptors and serotonin receptors. Its antiserotonergic action can increase appetite, which is why it is commonly used as an appetite stimulant in syrup formulations.
Clinical Trials: Phase 1 clinical trial is critical especially for assessing what?
Answer: Safety and tolerability (Maximum Tolerable Dose) in healthy volunteers.
Explanation: Phase 1 studies primarily evaluate safety, tolerability, pharmacokinetics, and dose range. They are usually conducted in healthy volunteers to identify the maximum tolerated dose.
Cardiovascular Drugs: Which drug is administered intravenously for the rapid treatment of PSVT (Paroxysmal Supraventricular Tachycardia)?
Answer: Adenosine.
Explanation: Adenosine is given by rapid IV bolus because it has a very short half-life. It transiently blocks AV nodal conduction and is the drug of choice for acute termination of PSVT.
Adverse Effects: Hemolytic anemia and methemoglobinemia are adverse effects of which drug?
Answer: Dapsone.
Explanation: Dapsone can produce oxidative stress in red blood cells, leading to hemolysis and methemoglobinemia. The risk is higher in patients with G6PD deficiency.
Oral Hypoglycemics: Acarbose, Voglibose, and Miglitol belong to which class?
Answer: Alpha-glucosidase inhibitors.
Explanation: These drugs inhibit intestinal alpha-glucosidase enzymes and delay carbohydrate digestion. As a result, they reduce postprandial blood glucose rise.
Insulin: Which of the following is a rapid-acting insulin?
Answer: Glulisine.
Explanation: Glulisine is a rapid-acting insulin analogue with quick onset and short duration of action. It is used around mealtime to control postprandial glucose levels.
Hormones: Which is the most active form of estrogen?
Answer: Estradiol (E2).
Explanation: Estradiol is the most potent natural estrogen in women of reproductive age. It has stronger estrogenic activity than estrone and estriol.
Diuretics: The diuretic action of Triamterene on the distal convoluted tubule is due to?
Answer: Inhibition of renal epithelial sodium channels.
Explanation: Triamterene is a potassium-sparing diuretic that blocks epithelial sodium channels in the late distal tubule and collecting duct. This reduces sodium reabsorption while conserving potassium.
Antidotes: What is the antidote for Cyclophosphamide-induced hemorrhagic cystitis?
Answer: Mesna.
Explanation: Cyclophosphamide produces acrolein, a toxic metabolite that irritates the bladder. Mesna binds and detoxifies acrolein, preventing hemorrhagic cystitis.
Tocolytics: Ritodrine acts as a uterine relaxant by targeting which receptors?
Answer: Beta-2 receptor agonist.
Explanation: Ritodrine stimulates beta-2 adrenergic receptors in uterine smooth muscle. This causes relaxation of the uterus and helps delay premature labor.
Antiarrhythmics: Quinidine and Procainamide block sodium channels in which state?
Answer: The open state.
Explanation: Quinidine and Procainamide are class IA antiarrhythmic drugs. They block voltage-gated sodium channels during depolarization and slow impulse conduction in cardiac tissue.
Serotonin Receptors: Match the drug to its receptor action.
Answer: Sumatriptan (5-HT1 agonist), Ketanserin (5-HT2 antagonist), Ondansetron (5-HT3 antagonist).
Explanation: Sumatriptan is used in migraine and acts on 5-HT1 receptors. Ketanserin blocks 5-HT2 receptors, while Ondansetron is a selective 5-HT3 antagonist used as an antiemetic.
Anti-TB Drugs: Which first-line anti-tubercular drug causes visual disturbances (red-green color blindness)?
Answer: Ethambutol.
Explanation: Ethambutol can cause optic neuritis, leading to decreased visual acuity and red-green color blindness. This is a classic adverse effect tested in pharmacology.
Calcium Channel Blockers: Which drug belongs to the dihydropyridine group?
Answer: Amlodipine / Nifedipine.
Explanation: Dihydropyridine calcium channel blockers mainly act on vascular smooth muscle and cause vasodilation. Common examples include Nifedipine and Amlodipine.
Immunosuppressants: What is the mechanism of Cyclosporine?
Answer: Calcineurin inhibitor (decreases Interleukin-2).
Explanation: Cyclosporine binds to cyclophilin and inhibits calcineurin. This suppresses T-cell activation by reducing IL-2 transcription.
Hypersensitivity: A boy presents with cough, sneezing, bronchoconstriction, and eosinophilia. Which type of hypersensitivity is this?
Answer: Type 1 Hypersensitivity (IgE mediated).
Explanation: Type 1 hypersensitivity is an immediate allergic reaction mediated by IgE antibodies and mast cell degranulation. It commonly presents with bronchospasm, sneezing, and eosinophilia.
Drug Interactions: Interaction of Methotrexate with Sulfonamides leads to?
Answer: Displacement of Methotrexate from plasma protein binding sites, increasing its toxicity.
Explanation: Sulfonamides can displace Methotrexate from plasma proteins and may also reduce its renal elimination. This increases free Methotrexate levels and toxicity risk.
Antipsychotic Complications: Clozapine administration is highly associated with which major risk?
Answer: Agranulocytosis / Blood dyscrasia.
Explanation: Clozapine is highly effective in resistant schizophrenia but carries a serious risk of agranulocytosis. Therefore, regular blood count monitoring is essential.
NSAID Side Effects: Long-term use of NSAIDs may induce edema and block antihypertensive actions due to?
Answer: Inhibition of renal prostaglandins leading to sodium and water retention.
Explanation: NSAIDs reduce prostaglandin synthesis in the kidney, decreasing renal blood flow and promoting sodium and water retention. This can worsen edema and reduce the effect of antihypertensive drugs.
Nerve Physiology: Action potentials in nerve fibers are unidirectional primarily due to?
Answer: Inactivation of voltage-gated sodium channels during the refractory period.
Explanation: After a segment of membrane depolarizes, its sodium channels become inactivated for a short period. This refractory state prevents backward propagation of the action potential.
Nerve Impulses: What is the correct direction of nerve impulse transmission?
Answer: Dendrites → Cell Body (Soma) → Axon → Axon terminal.
Explanation: In a neuron, incoming signals are received by dendrites, processed in the soma, conducted through the axon, and finally transmitted from the axon terminal to the next cell.
Respiratory System: The maximum amount of air that can be forcefully inhaled is called?
Answer: Inspiratory Reserve Volume (IRV).
Explanation: Inspiratory Reserve Volume is the additional amount of air that can be inhaled after a normal tidal inspiration. It reflects the reserve capacity of the lungs during inspiration.
GI Hormones: Endocrine cells in the intestinal mucosal layer secrete?
Answer: Secretin and Cholecystokinin (CCK).
Explanation: Specialized enteroendocrine cells in the intestinal mucosa release hormones such as secretin and CCK. These hormones regulate pancreatic secretion, bile release, and digestive activity.
Bone Physiology: Which cells are responsible for bone resorption?
Answer: Osteoclasts.
Explanation: Osteoclasts are multinucleated cells that break down bone matrix during bone resorption. Their action is balanced by osteoblasts, which form new bone.
Bone Structure: The part of the bone that withstands bending stress and provides a structural framework?
Answer: Compact bone (Osteons).
Explanation: Compact bone is dense and organized into osteons, making it strong and resistant to bending forces. It provides the major structural support of long bones.
Pregnancy: The hormone that prepares the endometrium for implantation of a fertilized egg?
Answer: Progesterone.
Explanation: Progesterone converts the proliferative endometrium into a secretory endometrium, making it suitable for implantation and maintenance of early pregnancy.
Cell Injury: Which type of necrosis is most commonly associated with bacterial infection and pus formation?
Answer: Liquefactive necrosis.
Explanation: Liquefactive necrosis occurs when tissue is digested by hydrolytic enzymes, producing a soft, liquid mass. It is classically seen in bacterial infections and abscess formation.
Pharmaceutical Chemistry & Analysis
Baeyer Strain Theory: Which is the most strained cycloalkane?
Answer: Cyclopropane.
Explanation: Cyclopropane has maximum angle strain because its bond angles are forced to 60°, far from the ideal tetrahedral angle of 109.5°. This makes it highly strained and reactive.
Name Reactions: Beckmann rearrangement converts what into what?
Answer: Oximes into amides.
Explanation: In Beckmann rearrangement, oximes undergo acid-catalyzed rearrangement to form amides. Cyclic ketoximes give lactams in this reaction.
Oxidation Reactions: Benzene, when oxidized with Vanadium pentoxide (V2O5), yields?
Answer: Maleic anhydride.
Explanation: Catalytic oxidation of benzene with vanadium pentoxide is an important industrial process for producing maleic anhydride, a valuable chemical intermediate.
Stereochemistry: What is the most stable conformation of ethane?
Answer: Staggered conformation.
Explanation: In the staggered conformation, hydrogen atoms are as far apart as possible, minimizing torsional strain. Therefore, it is more stable than the eclipsed conformation.
Acid Strength: Arrange by most acidic carboxylic acid.
Answer: Formic acid > Ethanoic acid > Propanoic acid.
Explanation: Formic acid is the strongest because it has no electron-donating alkyl group. Alkyl groups show a +I effect, which decreases acidity in ethanoic and propanoic acid.
Electrophilic Substitution: Which is most reactive towards electrophilic substitution?
Answer: Pyrrole > Furan > Thiophene > Pyridine.
Explanation: Pyrrole is the most electron-rich heteroaromatic ring among these, so it reacts fastest in electrophilic substitution. Pyridine is least reactive because its ring nitrogen withdraws electron density.
Chemical Bonding: Number of covalent bonds in Butane and Hexane?
Answer: Butane has 13, Hexane has 19.
Explanation: Butane (C4H10) has 3 C-C bonds and 10 C-H bonds, totaling 13 covalent bonds. Hexane (C6H14) has 5 C-C bonds and 14 C-H bonds, totaling 19.
Limit Tests: What is the internal diameter of the glass tube in the limit test for Arsenic?
Answer: 6.5 mm.
Explanation: In the Gutzeit apparatus used for the arsenic limit test, the internal diameter of the glass tube is standardized at 6.5 mm for proper development and comparison of the stain.
Dakin Reaction: Dakin oxidation converts aldehydes/ketones with ortho/para OH groups into?
Answer: Catechol derivatives.
Explanation: Dakin oxidation acts on aromatic aldehydes or ketones carrying ortho or para hydroxyl groups, producing dihydroxybenzene derivatives under oxidative conditions.
Asymmetric Centers: Number of asymmetric carbon atoms in Oxytetracycline?
Answer: 6.
Explanation: Oxytetracycline contains multiple stereogenic centers in its fused ring system. Correct identification of chiral centers is a common medicinal chemistry question.
Structure Configuration: Configuration of C8 and C9 in Quinine?
Answer: 8S, 9R.
Explanation: Quinine has defined stereochemistry that is important for its biological activity. The accepted configuration at these centers is 8S and 9R.
Drug Nucleus: Which ring is present in Nalidixic acid?
Answer: Naphthyridine ring.
Explanation: Nalidixic acid is the prototype quinolone-type antibacterial and structurally contains a naphthyridine nucleus. Recognition of core drug scaffolds is a common GPAT topic.
Complexometric Titrations: Indicator used for Magnesium and Calcium?
Answer: Eriochrome Black T.
Explanation: Eriochrome Black T is widely used in EDTA titrations of calcium and magnesium. It forms a colored complex with metal ions and gives a distinct endpoint color change.
Titration: Why is Potassium permanganate (KMnO4) called a self-indicator?
Answer: It produces a pale purple/pink color at the end point.
Explanation: KMnO4 has an intense purple color, so no external indicator is needed. The endpoint is indicated by the appearance of a faint permanent pink color.
Hammett Equation: A negative Sigma constant in the Hammett equation indicates?
Answer: An electron-donating group.
Explanation: In the Hammett equation, a negative sigma value means the substituent donates electron density relative to hydrogen. Such groups generally decrease the electron-withdrawing character of the ring system.
Chromatography: High molecular mass drugs (proteins, polymers) are determined by?
Answer: Gel permeation chromatography (Size-exclusion).
Explanation: Gel permeation or size-exclusion chromatography separates molecules based on size. It is especially useful for high molecular weight substances such as proteins and polymers.
Local Anesthetics: Which anesthetic contains a quinoline nucleus?
Answer: Dibucaine (Cinchocaine).
Explanation: Dibucaine is an amide local anesthetic known for its quinoline nucleus. Such structural identification is frequently asked in medicinal chemistry.
SAR of Benzodiazepines: Adding an electron-withdrawing group at position 7 results in?
Answer: Increased anxiolytic activity and CNS penetration.
Explanation: In benzodiazepine SAR, an electron-withdrawing group at the 7-position enhances receptor affinity and pharmacological activity. This substitution is important for optimal CNS effects.
Pharmaceutics, Physical Pharmacy & Pharmaceutical Engineering
Solubility Terms: "Sparingly soluble" means one part of solute dissolves in how many parts of solvent?
Answer: 30 to 100 parts.
Explanation: In pharmacopoeial terminology, sparingly soluble means one part of solute requires 30 to 100 parts of solvent for dissolution.
Solubility Terms: "Soluble" means one part of solute dissolves in how many parts of solvent?
Answer: 10 to 30 parts.
Explanation: The term soluble indicates that one part of solute dissolves in 10 to 30 parts of solvent under specified conditions.
Ophthalmic Buffers: Most commonly used buffer in ophthalmic preparations?
Answer: Phosphate buffer.
Explanation: Phosphate buffer is widely used in ophthalmic formulations because it maintains pH effectively and is generally well tolerated by the eye.
Transdermal Drug Delivery: Which is a chemical penetration enhancer?
Answer: Dimethyl sulfoxide (DMSO).
Explanation: DMSO enhances transdermal absorption by disrupting the barrier properties of the stratum corneum, thereby increasing drug penetration through the skin.
Quality Control: Methylene blue test is used for?
Answer: Ampoule leaker test.
Explanation: The methylene blue dye test checks container closure integrity in sealed ampoules. If there is a leak, the dye enters the ampoule and indicates a defect.
Aseptic Area: Laminar air flow cabinets provide which class of clean area?
Answer: Class 100 area.
Explanation: Laminar airflow cabinets provide a highly clean environment equivalent to Class 100 conditions, suitable for aseptic preparation and sterile compounding.
Sterilization: Sterility testing of antibiotic parenterals is performed by?
Answer: Membrane filtration method.
Explanation: Membrane filtration is preferred for antibiotic injections because the drug can inhibit microbial growth in direct inoculation methods. Filtration helps separate the drug from the test medium.
Ampoule Sealing: Nitrogen flushing is used during ampoule sealing to?
Answer: Reduce oxidation.
Explanation: Nitrogen displaces oxygen from the headspace of ampoules. This minimizes oxidation of oxygen-sensitive drugs during storage.
Tablet Defects: Tablet thickness variation is mainly influenced by?
Answer: Compression force.
Explanation: Compression force directly affects how tightly the powder bed is compacted. Higher force generally produces thinner and harder tablets.
Syrups: Inversion of sucrose due to excessive heating leads to?
Answer: Darkening of the syrup.
Explanation: Excessive heating hydrolyzes sucrose into invert sugar and may promote further decomposition or caramelization, causing darkening of the syrup.
Soft Gelatin Capsules: Which factor limits the batch size during manufacturing?
Answer: Drying time.
Explanation: In soft gelatin capsule production, drying is a major rate-limiting step. Large batches require more time and space for controlled drying.
Packaging: Most suitable packaging for a drug with high moisture uptake?
Answer: Alu-Alu blister pack.
Explanation: Alu-Alu packaging provides an excellent barrier against moisture, oxygen, and light. It is ideal for hygroscopic and moisture-sensitive drugs.
Distillation: Equilibrium distillation is also known as?
Answer: Flash distillation.
Explanation: In flash distillation, a liquid mixture is partially vaporized and allowed to reach vapor-liquid equilibrium in a single stage. Hence it is also called equilibrium distillation.
Size Reduction: Kick's Law states that energy required is directly proportional to?
Answer: Size reduction ratio.
Explanation: Kick's Law is mainly applied to coarse crushing and states that the energy required depends on the ratio of initial size to final size.
Evaporation: In a rising film evaporator, the liquid movement is due to?
Answer: Vapors lifting/rising.
Explanation: In a rising film evaporator, vapor generated inside the tube pushes the liquid upward as a thin film. This improves heat transfer and evaporation efficiency.
Emulsions: Creaming in emulsions is best described as?
Answer: Reversible phase separation due to the density difference of globules.
Explanation: Creaming occurs when dispersed droplets rise or settle because of density differences, but the droplets do not merge. It is reversible on shaking, unlike cracking.
Surfactants: Solubilizing agents have an HLB value of?
Answer: 15 to 18.
Explanation: High HLB surfactants are more hydrophilic and are effective as solubilizing agents. The usual HLB range for solubilization is around 15 to 18.
Surfactants: The concentration plateau at which surface tension no longer decreases is?
Answer: Critical Micelle Concentration (CMC).
Explanation: Once the surfactant concentration reaches the CMC, additional molecules form micelles rather than further lowering surface tension.
Pharmacokinetics: Formula for renal clearance?
Answer: Elimination rate divided by Plasma Drug Concentration.
Explanation: Renal clearance expresses the volume of plasma cleared of drug by the kidneys per unit time. It is calculated from urinary excretion rate divided by plasma concentration.
Pharmacokinetics: Wagner-Nelson method is used to determine?
Answer: Absorption rate constant.
Explanation: The Wagner-Nelson method is used in one-compartment pharmacokinetic models to estimate the fraction of drug absorbed and the absorption rate constant.
Compartment Modeling: In a two-compartment model, the central compartment represents?
Answer: Highly perfused organs (Heart, Lungs, Liver, Brain, Kidneys).
Explanation: The central compartment contains blood and well-perfused tissues where the drug distributes rapidly after administration.
Pharmacognosy
Chemical Tests: Which test for Aloe is based upon fluorescence?
Answer: Borax test (Schonteten's test).
Explanation: The borax test for Aloe gives a characteristic fluorescence and is used as an identification test for anthraquinone-containing material.
Alkaloids: Why does caffeine not give a precipitate with general alkaloid tests?
Answer: It is a purine derivative (pseudoalkaloid).
Explanation: Caffeine is a purine alkaloid and behaves differently from many typical alkaloids in general precipitation reactions. Therefore, it may not respond to usual alkaloid reagents in the same way.
Standardization: WHO recommends which chromatographic technique for herbal medicine fingerprinting?
Answer: HPTLC (High-Performance Thin-Layer Chromatography).
Explanation: HPTLC is widely used in herbal standardization because it is suitable for fingerprint profiling of complex plant extracts and helps confirm authenticity and consistency.
Leaf Constants: Which quantitative value does not remain constant throughout the age of the plant?
Answer: Stomatal number.
Explanation: Stomatal number can vary with age and environmental conditions. In contrast, the stomatal index is generally considered more constant.
Drug Interactions: Ginkgo biloba should be avoided with?
Answer: Warfarin.
Explanation: Ginkgo may increase bleeding tendency, and when combined with Warfarin the bleeding risk becomes more significant. This interaction is clinically important.
Biosynthesis: Taxol is primarily semi-synthesized from which precursor?
Answer: 10-Deacetylbaccatin III.
Explanation: 10-Deacetylbaccatin III is an important precursor used in the semi-synthesis of Taxol. It is obtained from renewable yew plant sources.
Phytoconstituents: Lycopene is classified as?
Answer: A carotenoid pigment.
Explanation: Lycopene is a red-colored carotenoid and an unsaturated hydrocarbon pigment found in tomatoes and other fruits. It is well known for antioxidant properties.
Microbiology, Biotechnology & Jurisprudence
Vitamin B12: Which microorganism is used in the assay/standardization of Vitamin B12?
Answer: Lactobacillus leichmannii.
Explanation: Lactobacillus leichmannii requires Vitamin B12 for growth and is therefore used in microbiological assay and standardization of the vitamin.
Vitamin B12: Which microorganism is used in the industrial production of Vitamin B12?
Answer: Pseudomonas denitrificans.
Explanation: Pseudomonas denitrificans is widely used in industrial fermentation for the production of Vitamin B12 because of its high yield efficiency.
Sterilization: Which gas is highly explosive but used for room fumigation?
Answer: Ethylene oxide.
Explanation: Ethylene oxide is a powerful gaseous sterilant used for heat-sensitive materials, but it is highly flammable and explosive, so strict handling precautions are necessary.
Sterilization: Commercial gamma radiation is not used for?
Answer: Heat-labile liquids.
Explanation: Gamma radiation is mainly used for sterilizing disposable medical supplies and packaged items. It is not generally used for bulk heat-labile liquids in routine pharmaceutical practice.
Jurisprudence: Schedule E of the Drugs and Cosmetics Act relates to?
Answer: List of Poisonous substances.
Explanation: Schedule E includes poisonous substances that require special caution in labeling and handling under the Drugs and Cosmetics Rules.
Jurisprudence: Form number for the registration certificate for the import of cosmetics?
Answer: Form 43.
Explanation: Form 43 is the prescribed registration certificate form associated with import regulation of cosmetics under Indian drug and cosmetic law.
Jurisprudence: CDSCO is regulated by?
Answer: Ministry of Health and Family Welfare.
Explanation: CDSCO functions under the Ministry of Health and Family Welfare, Government of India, and is the central regulatory authority for drugs, cosmetics, and medical devices.
These GPAT 2026 memory-based questions with answers and explanations can help you identify the most tested concepts and revise quickly before upcoming pharmacy entrance exams. Keep practicing subject-wise recall questions to strengthen concept retention and exam confidence.
I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
Mail- Sachin@pharmacyfreak.com