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Mongolia Pharmacist Licensing Exam study materials
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Mongolia Pharmacist Licensing Exam practice questions

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Question 1Pharmaceutical Chemistry and Medicinal Chemistry

Which functional group is present in acetylsalicylic acid (aspirin) but absent in salicylic acid?

  1. A carboxylic acid group on the aromatic ring
  2. An ester group formed at the phenolic hydroxyl Correct answer.
  3. A phenolic hydroxyl group
  4. An aromatic ring

Explanation

Aspirin is made by acetylating the phenolic hydroxyl of salicylic acid, which converts that OH into an acetate ester. Salicylic acid already contains the ring carboxylic acid and the free phenol, so the distinguishing group is the phenolic ester.

Question 2Pharmaceutical Chemistry and Medicinal Chemistry

Paracetamol (acetaminophen) is best classified chemically as which type of compound?

  1. An ester of salicylic acid
  2. An acetanilide-type amide of a phenol Correct answer.
  3. A sulfonamide
  4. A barbiturate

Explanation

Paracetamol is N-acetyl-p-aminophenol, i.e. an amide (acetamide) attached to a benzene ring bearing a hydroxyl group. Its characteristic structural feature is the phenolic OH para to the acetamido group.

Question 3Pharmaceutical Chemistry and Medicinal Chemistry

The pKa of a weakly acidic drug is 4.5. In which environment is the largest fraction of the drug ionized?

  1. A solution buffered at pH 4.5
  2. A solution buffered at pH 3.0
  3. Gastric fluid at pH 1.5
  4. Plasma at pH 7.4 Correct answer.

Explanation

For a weak acid, the fraction ionized rises as pH moves above the pKa. At pH 7.4 the difference from pKa is about 2.9 units, so the ionized form predominates heavily. At pH 4.5 the acid is only half ionized.

Question 4Pharmaceutical Chemistry and Medicinal Chemistry

Which heterocyclic ring system forms the core of the penicillin antibiotics?

  1. A gamma-lactam fused to a pyrrolidine ring
  2. A beta-lactam fused to a dihydrothiazine ring
  3. A beta-lactam fused to a thiazolidine ring Correct answer.
  4. A beta-lactam fused to an imidazolidine ring

Explanation

Penicillins contain a four-membered beta-lactam ring fused to a five-membered sulfur-containing thiazolidine ring. The related cephalosporins instead have a six-membered dihydrothiazine ring.

Question 5Pharmaceutical Chemistry and Medicinal Chemistry

Which statement correctly describes a prodrug?

  1. A metabolite that causes toxicity
  2. An active drug that is excreted unchanged in urine
  3. An inactive derivative that is converted to the active agent in the body Correct answer.
  4. A drug that binds irreversibly to its receptor

Explanation

A prodrug is a chemically modified, pharmacologically inactive form designed to improve properties such as absorption or stability, and it must undergo biotransformation to release the active drug. Enalapril, converted to enalaprilat, is a classic example.

Question 6Pharmaceutical Chemistry and Medicinal Chemistry

Which structural change most increases the lipophilicity of a carboxylic acid drug and thereby tends to prolong its duration of action?

  1. Esterifying the carboxyl group with a long alkyl chain Correct answer.
  2. Adding a quaternary ammonium group
  3. Converting the acid to a sodium salt
  4. Adding a hydroxyl group to the ring

Explanation

Esterification removes the ionizable carboxyl proton and adds a lipophilic alkyl chain, raising the partition coefficient and slowing clearance. This is the basis of many ester prodrugs and long-acting depot forms.

Question 7Pharmaceutical Chemistry and Medicinal Chemistry

Which analytical method is based on measuring the absorption of ultraviolet or visible light by a drug solution?

  1. Potentiometric titration
  2. UV-visible spectrophotometry Correct answer.
  3. Gas chromatography
  4. Mass spectrometry

Explanation

UV-visible spectrophotometry quantifies a compound from its absorbance according to the Beer-Lambert law, relating absorbance to concentration and path length. It requires a chromophore that absorbs in the relevant region.

Question 8Pharmaceutical Chemistry and Medicinal Chemistry

The IUPAC-style name 2-acetoxybenzoic acid corresponds to which drug?

  1. Paracetamol
  2. Ibuprofen
  3. Acetylsalicylic acid Correct answer.
  4. Methyl salicylate

Explanation

The benzoic acid core with an acetoxy (O-acetyl) substituent at position 2 is acetylsalicylic acid, i.e. aspirin. The acetoxy group sits on the ring carbon adjacent to the carboxyl group.

Question 9Pharmaceutical Chemistry and Medicinal Chemistry

A weak base drug with pKa 8.0 is placed in gastric fluid at pH 2.0. Which form predominates?

  1. Equal amounts of both forms
  2. The drug is completely degraded
  3. The ionized conjugate acid Correct answer.
  4. The unionized free base

Explanation

For a weak base, the protonated (ionized) form dominates when pH is well below the pKa. At pH 2.0, six units below pKa 8.0, the Henderson-Hasselbalch ratio strongly favors the conjugate acid.

Question 10Pharmaceutical Chemistry and Medicinal Chemistry

Which structural feature of sulfonamide antibacterials is required for their antimicrobial action?

  1. A free primary aromatic amino group para to the sulfonamide Correct answer.
  2. A carboxyl group adjacent to the sulfonamide
  3. An unsubstituted aliphatic amine
  4. A quaternary nitrogen

Explanation

Sulfonamides act as antimetabolites of p-aminobenzoic acid, so a free primary aromatic amine para to the sulfonamide group is needed to mimic PABA. Masking that amine, as in prodrugs like sulfasalazine, reduces activity until it is released.

Question 11Pharmaceutical Chemistry and Medicinal Chemistry

Which phase II metabolic reaction conjugates drugs with glucuronic acid?

  1. Acetylation catalyzed by N-acetyltransferase
  2. Sulfation catalyzed by sulfotransferase
  3. Glucuronidation catalyzed by UDP-glucuronosyltransferase Correct answer.
  4. Methylation catalyzed by catechol O-methyltransferase

Explanation

Glucuronidation transfers glucuronic acid from UDP-glucuronic acid to nucleophilic groups such as hydroxyl or carboxyl, catalyzed by UDP-glucuronosyltransferases. The resulting glucuronide is polar and readily excreted.

Question 12Pharmaceutical Chemistry and Medicinal Chemistry

A racemic drug is administered, and only the (S)-enantiomer shows high affinity for the target receptor. What is the most likely consequence?

  1. The (R)-enantiomer is always pharmacologically inert in every tissue
  2. Racemic mixtures cannot be used clinically
  3. Both enantiomers are equipotent at the receptor
  4. The (R)-enantiomer contributes little receptor-mediated efficacy but may add distinct off-target effects Correct answer.

Explanation

Enantiomers differ in three-dimensional fit at chiral binding sites, so receptor affinity is usually stereoselective. The distomer may be weak at the main target yet still interact with other receptors or transporters, producing separate effects.

Question 13Pharmaceutical Chemistry and Medicinal Chemistry

Which property of a drug molecule most directly determines its ability to cross lipid membranes by passive diffusion?

  1. Its melting point
  2. Its partition coefficient between octanol and water Correct answer.
  3. Its crystal color
  4. Its molecular weight alone

Explanation

Passive diffusion depends largely on lipophilicity, commonly estimated by the octanol-water partition coefficient (log P) together with the ionized fraction. Optimal log P balances membrane permeability against aqueous solubility.

Question 14Pharmaceutical Chemistry and Medicinal Chemistry

Which reaction is used to prepare an ester prodrug from a carboxylic acid drug and an alcohol?

  1. Fischer esterification under acid catalysis Correct answer.
  2. Reductive amination
  3. Nucleophilic aromatic substitution
  4. Grignard addition to a ketone

Explanation

Fischer esterification reacts a carboxylic acid with an alcohol in the presence of an acid catalyst, with water removal driving the equilibrium. It is the standard route to simple alkyl ester prodrugs.

Question 15Pharmaceutical Chemistry and Medicinal Chemistry

Which interaction most commonly stabilizes a drug at its receptor binding site through a hydrogen bond?

  1. Two methyl groups approaching each other
  2. Aromatic rings stacking face to face
  3. A fully ionized carboxylate near a negatively charged residue
  4. A hydroxyl group of the drug donating to a carbonyl oxygen of the protein backbone Correct answer.

Explanation

Hydrogen bonds form between a donor such as an OH or NH and an acceptor with a lone pair, and protein backbone carbonyls are common acceptors. This directional interaction contributes strongly to binding specificity.

Question 16Pharmaceutical Chemistry and Medicinal Chemistry

Which structural modification of a drug typically increases its water solubility for intravenous formulation?

  1. Adding a long hydrocarbon chain
  2. Forming a hydrochloride salt of a basic amine Correct answer.
  3. Increasing the number of aromatic rings
  4. Esterifying a hydroxyl with butyric acid

Explanation

Converting a basic amine into its hydrochloride salt gives an ionizable, crystalline solid with much higher aqueous solubility. Salt formation is a standard strategy for parenteral formulations of basic drugs.

Question 17Pharmaceutical Chemistry and Medicinal Chemistry

Which class of compounds includes morphine and codeine?

  1. Phenylpropylamine stimulants
  2. Beta-lactam antibiotics
  3. Phenanthrene alkaloids of opium Correct answer.
  4. Benzodiazepines

Explanation

Morphine and codeine are phenanthrene-type alkaloids isolated from opium poppy, sharing a fused tetracyclic framework. Their analgesic action arises from interaction with opioid receptors.

Question 18Pharmaceutical Chemistry and Medicinal Chemistry

A drug is a weak acid with pKa 3.0. Which statement about its absorption from the stomach (pH 1.5) versus the intestine (pH 6.5) is most accurate?

  1. It is largely ionized in the stomach but unionized in the intestine
  2. It is equally ionized in both compartments
  3. It is largely unionized in the stomach but largely ionized in the intestine Correct answer.
  4. It is unionized in both compartments

Explanation

Below the pKa the acid remains protonated and unionized, favoring gastric absorption; above the pKa it deprotonates and becomes ionized. At pH 6.5 the drug is about 3.5 units above pKa and therefore mainly ionized.

Question 19Pharmaceutical Chemistry and Medicinal Chemistry

Which analytical technique is most appropriate for confirming the identity of a drug substance by its molecular ion and fragmentation pattern?

  1. Mass spectrometry Correct answer.
  2. Potentiometric titration
  3. UV-visible spectrophotometry
  4. Polarimetry

Explanation

Mass spectrometry provides the molecular ion mass and a characteristic fragmentation pattern, which together support structural identification. It is widely used for confirmation and impurity characterization.

Question 20Pharmaceutical Chemistry and Medicinal Chemistry

Which statement best explains why enantiomers of a chiral drug can differ in pharmacological potency?

  1. Enantiomers always have different melting points
  2. The receptor binding site is chiral, so each enantiomer fits with different affinity Correct answer.
  3. Enantiomers have different molecular formulas
  4. Enantiomers differ in the number of hydrogen atoms

Explanation

Biological receptors are built from chiral amino acids and present a chiral environment, so the three-dimensional fit of each enantiomer differs, leading to different affinities and potencies. This is the basis of stereoselective drug action.

Question 21Pharmaceutical Chemistry and Medicinal Chemistry

Which biotransformation converts a pharmacologically active drug into a more polar, usually less active metabolite?

  1. Oxidation of a methyl group to a carboxylic acid Correct answer.
  2. Hydrolysis of an ester to an acid and alcohol
  3. Acetylation of an aromatic amine
  4. Reduction of a ketone to a secondary alcohol

Explanation

Oxidation of a methyl group to a carboxylic acid introduces a strongly ionizable polar group, markedly increasing water solubility and usually reducing activity. This is a common phase I functionalization step.

Question 22Pharmaceutical Chemistry and Medicinal Chemistry

Which feature distinguishes cephalosporins from penicillins at the structural level?

  1. A five-membered thiazolidine ring fused to the beta-lactam
  2. A single beta-lactam ring without any fused ring
  3. A macrolide lactone ring
  4. A six-membered dihydrothiazine ring fused to the beta-lactam Correct answer.

Explanation

Cephalosporins possess a beta-lactam fused to a six-membered dihydrothiazine ring, giving greater stability to some beta-lactamases than penicillins. Penicillins instead have the five-membered thiazolidine fusion.

Question 23Pharmaceutical Chemistry and Medicinal Chemistry

A drug is designed with a carboxylic acid (pKa 4.0) and a tertiary amine (pKa 9.0). At plasma pH 7.4, what is the net charge state of the molecule?

  1. Predominantly cationic with both groups protonated
  2. Predominantly anionic with both groups deprotonated
  3. Predominantly zwitterionic with a negative carboxylate and a protonated amine Correct answer.
  4. Predominantly neutral with both groups unionized

Explanation

At pH 7.4 the carboxyl acid (pKa 4.0) is deprotonated and negative, while the amine (pKa 9.0) remains protonated and positive. The molecule therefore exists mainly as a zwitterion with a net charge near zero.

Question 24Pharmaceutical Chemistry and Medicinal Chemistry

Which statement about the structure-activity relationship of beta-lactam antibiotics is most accurate?

  1. A free carboxyl group prevents binding to penicillin-binding proteins
  2. The beta-lactam ring is not involved in antibacterial activity
  3. Acylation of the beta-lactam carbonyl by a bacterial transpeptidase serine is central to antibacterial action Correct answer.
  4. The thiazolidine sulfur is the sole pharmacophore

Explanation

Beta-lactams act as suicide substrates: the strained beta-lactam carbonyl is attacked by the active-site serine of transpeptidases, acylating the enzyme and blocking cell-wall cross-linking. The intact beta-lactam ring is therefore essential for activity.

Question 25Pharmaceutical Chemistry and Medicinal Chemistry

Which metabolic pathway can convert a carboxylic acid drug into a glucuronide that undergoes enterohepatic recycling?

  1. Acyl glucuronidation of the carboxyl group, followed by biliary excretion and intestinal hydrolysis Correct answer.
  2. N-acetylation of the carboxyl group
  3. Oxidative deamination of the carboxyl group
  4. Sulfation of the aromatic ring only

Explanation

Carboxylic acids can form acyl glucuronides, which are excreted in bile; intestinal beta-glucuronidase can hydrolyze them, releasing the parent drug for reabsorption and prolonging exposure. This cycle is the basis of enterohepatic recycling.

Question 26Pharmaceutical Chemistry and Medicinal Chemistry

Which functional group is present in the structure of paracetamol (acetaminophen) and is responsible for its analgesic and antipyretic activity?

  1. Quaternary ammonium group
  2. Sulfonamide group
  3. Carboxylic acid group
  4. Phenolic hydroxyl group Correct answer.

Explanation

Paracetamol is an N-acetylated p-aminophenol, so its structure contains an amide, a benzene ring, and a phenolic hydroxyl group. The phenolic OH is the key ionizable and metabolically reactive group of the molecule. Neither a free carboxylic acid, a sulfonamide, nor a quaternary ammonium group appears in this structure.

Question 27Pharmaceutical Chemistry and Medicinal Chemistry

In medicinal chemistry, which physicochemical property is most directly used to predict how readily a drug distributes into lipid membranes?

  1. Partition coefficient (log P) Correct answer.
  2. Molecular weight measured by mass spectrometry
  3. Melting point of the crystalline solid
  4. Optical rotation measured by polarimetry

Explanation

The partition coefficient log P expresses the ratio of a drug's concentration in a lipid-like solvent (usually octanol) to its concentration in water. It therefore quantifies the balance of lipophilicity and hydrophilicity that governs passive membrane permeation. Molecular weight, optical rotation, and melting point do not directly describe this lipophilic-hydrophilic partition.

Question 28Pharmaceutical Chemistry and Medicinal Chemistry

A drug molecule contains a carboxylic acid group with pKa 4.5. At a physiological pH of 7.4, what is the approximate ratio of ionized (carboxylate) to unionized (carboxylic acid) forms?

  1. About 10:1
  2. About 1:1
  3. About 1000:1 Correct answer.
  4. About 1:1000

Explanation

The Henderson-Hasselbalch equation for an acid is pH = pKa + log([A-]/[HA]). With pH 7.4 and pKa 4.5, the difference is 2.9, so log([A-]/[HA]) = 2.9 and the ratio is roughly 10^2.9, close to 1000:1 in favor of the ionized carboxylate.

Question 29Pharmaceutical Chemistry and Medicinal Chemistry

Which statement about the structural requirements for beta-lactam antibacterial activity is correct?

  1. The carboxylate group of the thiazolidine ring can be removed without loss of activity.
  2. The fused beta-lactam ring must remain intact, and acylation of bacterial transpeptidases is required for activity. Correct answer.
  3. The beta-lactam ring must be opened by hydrolysis before the drug can bind its target.
  4. A free amino group on the side chain is essential for all beta-lactam classes.

Explanation

Beta-lactam antibacterials act by acylating the active-site serine of bacterial transpeptidases (penicillin-binding proteins), which requires an intact, strained beta-lactam ring. Hydrolysis of that ring destroys the reactive carbonyl and abolishes antibacterial activity. The free amino group and the carboxylate are important for some classes, but neither is universally essential.

Question 30Pharmaceutical Chemistry and Medicinal Chemistry

A carboxylic acid drug is administered orally as an ester prodrug. Which metabolic process regenerates the active parent drug after absorption?

  1. Ester hydrolysis catalyzed by carboxylesterases Correct answer.
  2. Oxidative N-dealkylation by cytochrome P450
  3. Reduction of a nitro group by intestinal bacteria
  4. Phase II glucuronidation by UDP-glucuronosyltransferase

Explanation

Ester prodrugs are designed to be hydrolyzed by esterases (such as carboxylesterases in plasma, liver, and intestinal mucosa) to release the active carboxylic acid and the promoiety. This biotransformation improves oral absorption by masking the polar acid group. Glucuronidation, N-dealkylation, and nitro reduction do not regenerate a carboxylic acid from an ester.

Question 31Pharmacognosy and Natural Product Pharmacy

Which plant family is the principal commercial source of tropane alkaloids such as hyoscyamine and scopolamine?

  1. Ranunculaceae
  2. Apiaceae
  3. Solanaceae Correct answer.
  4. Papaveraceae

Explanation

Tropane alkaloids are characteristic of the Solanaceae, being produced in Datura, Atropa, Hyoscyamus and Duboisia species. Apiaceae and Papaveraceae accumulate different classes of nitrogenous compounds, such as coumarins and isoquinoline alkaloids respectively.

Question 32Pharmacognosy and Natural Product Pharmacy

Which natural product is the standard precursor used for semisynthesis of the anticancer agent etoposide?

  1. Podophyllotoxin Correct answer.
  2. Vincristine
  3. Taxol
  4. Colchicine

Explanation

Podophyllotoxin, obtained from Podophyllum species, is the starting material for semisynthetic epipodophyllotoxin derivatives such as etoposide and teniposide. Taxol and vincristine are themselves used clinically but are not the precursors of etoposide.

Question 33Pharmacognosy and Natural Product Pharmacy

A pharmacognosy laboratory needs to confirm the presence of cardiac glycosides in a leaf extract. Which chemical test is most appropriate?

  1. Fehling test
  2. Dragendorff test
  3. Ninhydrin test
  4. Keller-Kiliani test Correct answer.

Explanation

The Keller-Kiliani reaction detects deoxy sugars of cardiac glycosides, giving a reddish-brown ring, and is a classic identification test for this group. Dragendorff reagent detects alkaloids, ninhydrin detects amino acids, and Fehling solution detects reducing sugars generally.

Question 34Pharmacognosy and Natural Product Pharmacy

Which alkaloid is obtained from the dried latex of unripe Papaver somniferum capsules?

  1. Reserpine
  2. Ephedrine
  3. Quinine
  4. Morphine Correct answer.

Explanation

Opium is the air-dried latex of unripe poppy capsules and its principal alkaloid is morphine, together with codeine, thebaine and papaverine. Quinine comes from Cinchona bark, reserpine from Rauwolfia root, and ephedrine from Ephedra.

Question 35Pharmacognosy and Natural Product Pharmacy

According to the WHO monographs, the active antimalarial alkaloid quinine is obtained from the bark of which genus?

  1. Cinchona Correct answer.
  2. Rauwolfia
  3. Salix
  4. Strychnos

Explanation

Cinchona bark contains quinoline alkaloids, principally quinine and quinidine, and is the classical antimalarial crude drug. Salix bark yields salicin, Rauwolfia yields reserpine-type indole alkaloids, and Strychnos yields strychnine.

Question 36Pharmacognosy and Natural Product Pharmacy

Which statement best describes the role of the Mevalonate pathway in plant secondary metabolism?

  1. It supplies isopentenyl diphosphate for biosynthesis of terpenoids Correct answer.
  2. It decarboxylates ornithine to form putrescine
  3. It converts shikimic acid into aromatic amino acids
  4. It oxidizes phenylpropanoids to coumarins

Explanation

The mevalonate pathway produces isopentenyl diphosphate and dimethylallyl diphosphate, the C5 building blocks for terpenoid biosynthesis. The shikimate pathway generates aromatic amino acids and phenylpropanoids, while ornithine decarboxylation supplies tropane and pyrrolizidine alkaloid precursors.

Question 37Pharmacognosy and Natural Product Pharmacy

A crude drug sample is suspected to be adulterated with exhausted material. Which quality indicator most directly reveals this?

  1. A high moisture content
  2. An abnormally low content of the marker active constituent Correct answer.
  3. Presence of foreign organic matter
  4. An elevated total ash value

Explanation

Exhausted material has already had its soluble active constituents removed, so assay of the marker compound shows a markedly reduced content. Ash, moisture and foreign matter indicate other types of impurity and do not by themselves demonstrate extraction of the active principle.

Question 38Pharmacognosy and Natural Product Pharmacy

Which solvent is most commonly used for the initial extraction of volatile oils from fresh plant material by hydrodistillation?

  1. Water Correct answer.
  2. Chloroform
  3. Ethanol
  4. Hexane

Explanation

Hydrodistillation uses water or steam as the immiscible carrier phase, and the volatile oil is collected after condensation. Organic solvents such as hexane are used in solvent extraction but not in hydrodistillation.

Question 39Pharmacognosy and Natural Product Pharmacy

Which constituent is responsible for the characteristic pungency of Capsicum fruits and is used as a marker in their standardization?

  1. Curcumin
  2. Capsaicin Correct answer.
  3. Piperine
  4. Gingerol

Explanation

Capsaicin is the vanillylamide responsible for the pungency of Capsicum and is used as the marker for its assay. Piperine gives pepper its pungency, gingerol is the pungent principle of ginger, and curcumin is the yellow colouring constituent of turmeric.

Question 40Pharmacognosy and Natural Product Pharmacy

Which plant is the official source of the laxative anthraquinone drug senna?

  1. Plantago ovata
  2. Cassia angustifolia Correct answer.
  3. Aloe vera
  4. Rheum palmatum

Explanation

Senna consists of the dried leaflets of Cassia angustifolia or Cassia acutifolia, whose dianthrone glycosides (sennosides) give the laxative action. Aloe and rhubarb also contain anthraquinones but are distinct official drugs, while Plantago ovata supplies mucilage.

Question 41Pharmacognosy and Natural Product Pharmacy

Digitalis purpurea leaves are standardized mainly on the content of which class of constituents?

  1. Saponins
  2. Flavonoids
  3. Cardiac glycosides Correct answer.
  4. Tannins

Explanation

Digitalis leaves are assayed for cardiac glycosides such as digitoxin and gitoxin, which are the cardiotonic principles. Tannins, saponins and flavonoids may be present but do not define the pharmacopoeial potency of the drug.

Question 42Pharmacognosy and Natural Product Pharmacy

A patient taking warfarin asks about a herbal product containing Ginkgo biloba. Which interaction concern is most relevant pharmacognostically?

  1. Reduction of warfarin absorption by mucilage
  2. Additive antiplatelet and bleeding risk Correct answer.
  3. Chelation of warfarin by tannins
  4. Induction of CYP3A4 lowering warfarin levels

Explanation

Ginkgo constituents, particularly ginkgolides, inhibit platelet-activating factor and may add to the anticoagulant effect of warfarin, increasing bleeding risk. Mucilage, enzyme induction and tannin chelation are not the recognized principal mechanism for this pair.

Question 43Pharmacognosy and Natural Product Pharmacy

Which alkaloid-bearing drug is traditionally used for its anticholinergic antispasmodic action on the gastrointestinal tract?

  1. Valeriana officinalis
  2. Glycyrrhiza glabra
  3. Digitalis purpurea
  4. Atropa belladonna Correct answer.

Explanation

Belladonna herb and root contain hyoscyamine, which acts as a muscarinic antagonist and relieves smooth muscle spasm. Digitalis is cardiotonic, liquorice is used as a demulcent and expectorant, and valerian is a sedative.

Question 44Pharmacognosy and Natural Product Pharmacy

Which technique is most suitable for fingerprinting the volatile oil profile of a peppermint sample for quality control?

  1. Gel electrophoresis
  2. Polarimetry
  3. Gas chromatography Correct answer.
  4. Atomic absorption spectroscopy

Explanation

Volatile oils consist of thermostable lipophilic compounds such as menthol and menthone, which are best separated and fingerprinted by gas chromatography. Atomic absorption measures metals, electrophoresis separates charged macromolecules, and polarimetry measures optical rotation only.

Question 45Pharmacognosy and Natural Product Pharmacy

In the biosynthesis of phenylpropanoid-derived compounds such as coumarins, which amino acid is the direct precursor?

  1. Lysine
  2. Tryptophan
  3. Phenylalanine Correct answer.
  4. Ornithine

Explanation

Phenylalanine is deaminated by phenylalanine ammonia-lyase to cinnamic acid, the entry point to phenylpropanoid metabolism and hence to coumarins and lignans. Tryptophan, ornithine and lysine feed indole and tropane or piperidine alkaloid pathways instead.

Question 46Pharmacognosy and Natural Product Pharmacy

Which statement correctly distinguishes a tincture from a fluid extract in pharmacognosy?

  1. A fluid extract contains no active constituents
  2. A tincture is always aqueous while a fluid extract is always alcoholic
  3. A tincture is usually prepared with alcohol at a lower drug-to-solvent ratio than a fluid extract Correct answer.
  4. A tincture is a dry powder while a fluid extract is a syrup

Explanation

Tinctures are typically 1:5 or 1:10 preparations in alcohol or hydroalcoholic solvent, whereas fluid extracts are concentrated 1:1 preparations. Both may be alcoholic, and neither is defined as a dry powder or a syrup.

Question 47Pharmaceutics, Dosage Form Design, and Compounding

Эмийн тоосонцрын хэмжээг багасгахад бодисын уусах хурд хэрхэн өөрчлөгдөх вэ?

  1. Уусах хурд өөрчлөгдөхгүй
  2. Уусах хурд зөвхөн температурaас хамаарна
  3. Гадаргуугийн талбай багассанaар уусах хурд нэмэгдэнэ
  4. Гадаргуугийн талбай ихэссэнээр уусах хурд нэмэгдэнэ Correct answer.

Explanation

Нунтаглалт нь нийт гадаргуугийн талбайг ихээхэн нэмэгдүүлдэг. Нернст-Бруннерын тэгшитгэлээр уусах хурд нь гадаргуугийн талбайтай шууд пропорциональ байдаг тул жижиг тоосонцор хурдан уусдаг.

Question 48Pharmaceutics, Dosage Form Design, and Compounding

Хатуу эмийн хэлбэрийн таблетка доторх бодисын жигд тархалтыг хангах үйлдлийг юу гэж нэрлэдэг вэ?

  1. Грануляци
  2. Шигшүүлэх
  3. Холих (mixнг) Correct answer.
  4. Шахалт

Explanation

Холих үйлдэл нь эмийн бодис болон туслах бодисыг жигд тархахад чиглэгддэг. Жигд бус холилт нь тунгийн нэгдмэл байдал алдагдахад хүргэдэг.

Question 49Pharmaceutics, Dosage Form Design, and Compounding

Эмульсийн тогтвортой байдлыг хангахын тулд тос, усны фазын хоорондох гадаргуугийн хүчдэлийг бууруулдаг бодисыг юу гэж нэрлэдэг вэ?

  1. Сусагшуулагч
  2. Антиоксидант
  3. Эмульгатор Correct answer.
  4. Консервант

Explanation

Эмульгатор нь гадаргуугийн идэвхт бодис бөгөөд тос, усны хил дээр хуримтлагдан гадаргуугийн хүчдэлийг бууруулж, эмульсийг тогтвортой байлгана.

Question 50Pharmaceutics, Dosage Form Design, and Compounding

Сав баглаа боодлын шошгон дээр эмийн хэлбэрийн хадгалах нөхцлийг зааж өгөхдөө аль мэдээлэл заавал байх ёстой вэ?

  1. Зөвхөн үнийн мэдээлэл
  2. Эмийн бодисын химийн бүтэц
  3. Үйлдвэрлэсэн огноо, хүчинтэй хугацаа Correct answer.
  4. Эмчийн утасны дугаар

Explanation

Эмийн хэлбэрийн аюулгүй байдал, чанарыг хангахын тулд үйлдвэрлэсэн огноо болон хүчинтэй хугацааг заавал тэмдэглэнэ. Хүчинтэй хугацаа хэтэрсэн эмийг хэрэглэхийг хориглодог.