Pharmacognosy, phytochemistry, natural products, herbal drug technology
8%
of the paper
≈ 40 marks
#5
by weightage
of 5 heads
1179
questions
with explanations
0
cite a source
reference material
Weightage follows the locked NBEMS GPAT blueprint (docs/12-GPAT-TAXONOMY.md), not an estimate. Question counts are read from the live bank when this page is built.
Subtopics in this bank
Alkaloid-, glycoside- and steroid/cardiac-glycoside-containing crude drugsBasics of phytochemistry: modern extraction, chromatography, spectroscopy and electrophoresisBiogenetic pathways of secondary metabolites and radioisotope tracer studiesClassification of crude drugsCultivation, collection, processing, storage and conservation of medicinal plantsEvaluation of herbal drugs: WHO and ICH guidelines and stability testingEvaluation of herbal drugs: WHO guidelines and stability testingHerbal cosmetics, herbal excipients and herbal formulations including phytosomesHerbs as raw materials: authentication, good agricultural practices and pest managementHerb–drug and herb–food interactionsIndian systems of medicine and standardization of Ayurvedic formulationsIntroduction to Pharmacognosy: definition, scope, sources of drugs, organized and unorganized drugsIsolation, identification and industrial production of named phytoconstituentsNutraceuticals and herbs used as health foodsPatenting, IPR, biopiracy and regulation of ASU drugs including Schedule T GMPPhenylpropanoids and flavonoids as secondary metabolitesPlant tissue culture and edible vaccinesPrimary metabolites and plant products as pharmaceutical aids: carbohydrates, proteins/enzymes, lipids, fibres and marine drugsQuality control of natural-origin drugs: adulteration and methods of evaluationQuantitative microscopy: leaf constants, lycopodium spore method and camera lucidaSecondary metabolites: definition, classification and identification testsVolatile oil-, tannin-, resin- and terpenoid-containing crude drugs
Sample questions, with the reasoning
Every question in the bank is explained like this — including why each wrong option is wrong.
A 20.0 g sample of a powdered alkaloidal crude drug is found to contain 8.0% w/w moisture on loss-on-drying. When the dried drug is assayed, its total alkaloid content is 2.5% w/w (i.e. calculated on the dried basis). What is the total alkaloid content expressed on the original (as-received) basis?
A)2.30% w/w✓
B)2.50% w/w
C)2.72% w/w
D)0.20% w/w
Why A is correct
On the as-received basis, 100 g of drug contains 92 g of dry matter (moisture = 8%). The dried drug is 2.5% alkaloid, so the alkaloid present is 2.5% of 92 g = 2.3 g per 100 g of original drug, i.e. 2.30% w/w. Converting a dried-basis assay to the as-received basis therefore requires multiplying by (1 − moisture fraction): 2.5 × 0.92 = 2.30%. (The 20.0 g total mass is not needed for a percentage result.)
AI fact-checked
A 3.0 g portion of a powdered crude drug is accurately weighed into a tared silica crucible (empty mass 25.000 g) and incinerated to constant mass. The crucible together with the residual ash then weighs 25.180 g. What is the total ash value of the drug (% w/w)?
A)6.0%✓
B)5.4%
C)0.6%
D)18.0%
Why A is correct
Mass of ash = 25.180 − 25.000 = 0.180 g. Total ash (% w/w) = (0.180 / 3.0) × 100 = 6.0%.
AI fact-checked
A balsam is defined pharmacognostically as a resinous product containing a high proportion of aromatic balsamic acids (cinnamic acid, benzoic acid) or their esters. On this basis, which of the following crude drugs is correctly classified as a TRUE balsam?
A)Tolu balsam (from Myroxylon balsamum)✓
B)Colophony (rosin)
C)Asafoetida
D)Myrrh
Why A is correct
Tolu balsam is obtained from Myroxylon balsamum and consists largely of free benzoic and cinnamic acids together with their benzyl/cinnamyl esters (and resin), which is exactly the compositional definition of a true balsam. The distractors are a pure resin (colophony) and two oleo-gum-resins (asafoetida, myrrh).
AI fact-checked
Practise G05 with real marking
1179 questions · +4/−1 NBEMS marking · explanations after every answer. No sign-up needed.