Introduction: Sources of herbs and their selection, identification and authentication are core topics in pharmacognosy for B.Pharm students. This study covers botanical sources, plant parts (leaf, root, rhizome, bark), geographical and seasonal influences, criteria for selection, and methods of identification and authentication including macroscopic, microscopic, organoleptic, physicochemical, phytochemical and DNA barcoding techniques. Emphasis is placed on quality control, detection of adulteration/substitution, voucher specimens, herbarium practices, and relevant pharmacopeial standards. Mastery of these concepts ensures reliable herbal drug supply, safe formulations and regulatory compliance. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which part of the pharmacognostic examination primarily uses visible features such as color, odor, size and surface texture?
- Microscopic examination
- Organoleptic examination
- Phytochemical screening
- DNA barcoding
Correct Answer: Organoleptic examination
Q2. Which of the following is NOT a standard parameter for crude drug quality assessment in pharmacognosy?
- Total ash value
- Foreign organic matter
- DNA melting temperature of active compound
- Extractive value
Correct Answer: DNA melting temperature of active compound
Q3. A herbarium voucher specimen is important because it:
- Quantifies active constituent concentration
- Serves as a permanent reference for botanical identification
- Directly measures pesticide residues
- Replaces the need for microscopic analysis
Correct Answer: Serves as a permanent reference for botanical identification
Q4. Which microscopic feature is most useful to distinguish leaf of Ocimum (basil) from other Lamiaceae members?
- Presence of vessel elements
- Type and distribution of glandular trichomes
- Starch grains in cortex
- Calcium oxalate raphides in xylem
Correct Answer: Type and distribution of glandular trichomes
Q5. Which chemical test is commonly used for preliminary detection of alkaloids in crude plant extracts?
- Benedict’s test
- Dragendorff’s test
- Froth test
- Salkowski’s test
Correct Answer: Dragendorff’s test
Q6. DNA barcoding for herbal authentication typically targets which type of sequence?
- Conserved chloroplast or nuclear DNA regions
- Mitochondrial protein-coding genes of animals
- Ribosomal RNA of bacteria
- Random genomic fragments without reference
Correct Answer: Conserved chloroplast or nuclear DNA regions
Q7. Which extractive value gives an estimate of polar constituents like glycosides and tannins?
- Alcohol-soluble extractive value
- Petroleum ether extractive value
- Water-insoluble ash
- Acid-insoluble ash
Correct Answer: Alcohol-soluble extractive value
Q8. Which microscopy stain is commonly used to reveal lignified cell walls in plant sections?
- Phloroglucinol-HCl (Wiesner reagent)
- Dragendorff reagent
- Biuret reagent
- Molisch reagent
Correct Answer: Phloroglucinol-HCl (Wiesner reagent)
Q9. Adulteration by substitution in herbal drugs means:
- Mixing permitted preservatives into the herb
- Replacing the genuine plant with a different species
- Reducing particle size for better extraction
- Standardizing active marker compounds
Correct Answer: Replacing the genuine plant with a different species
Q10. Which pharmacopoeial parameter assesses inorganic residue remaining after incineration of a herbal drug?
- Extractive value
- Total ash value
- Moisture content
- Chromatographic purity
Correct Answer: Total ash value
Q11. Which chromatographic technique is widely used for fingerprinting and comparative identification of herbal extracts?
- TLC/HPTLC
- Paper electrophoresis
- Gel filtration chromatography on agarose
- Isoelectric focusing
Correct Answer: TLC/HPTLC
Q12. Anisocytic stomata count and type are examples of which identification method?
- Organoleptic evaluation
- Macroscopic morphology
- Microscopic anatomy
- Phytochemical screening
Correct Answer: Microscopic anatomy
Q13. Which parameter helps detect sandy impurities and siliceous contamination in herbal drugs?
- Acid-insoluble ash
- Water-soluble extractive
- Loss on drying
- pH of aqueous extract
Correct Answer: Acid-insoluble ash
Q14. Which of the following best describes chemotaxonomy in herbal identification?
- Use of chemical constituents to support plant classification
- Microscopic staining of vascular tissues
- Use of DNA sequences only for identification
- Organoleptic comparison using taste panels
Correct Answer: Use of chemical constituents to support plant classification
Q15. The presence of saponins in an extract is commonly detected by which preliminary test?
- Froth test (persistent foam)
- Dragendorff’s test
- Fehling’s test
- Bromine water test
Correct Answer: Froth test (persistent foam)
Q16. Which of the following is a reliable molecular tool for distinguishing closely related plant species used as herbs?
- UV-visible spectroscopy
- RAPD without sequencing reference
- DNA barcoding with ITS or rbcL markers
- Thin layer chromatography alone
Correct Answer: DNA barcoding with ITS or rbcL markers
Q17. Which water content parameter is critical to prevent microbial growth and enzymatic degradation in stored herbs?
- Acid-insoluble ash
- Loss on drying or moisture content
- Alcohol-soluble extractive value
- Organoleptic score
Correct Answer: Loss on drying or moisture content
Q18. Which of these is a common sign of powdered herb adulteration visible under a microscope?
- Uniform cell types matching pure reference
- Presence of foreign cell fragments like starch granules or fibers
- High TLC similarity with genuine herb
- Low acid-insoluble ash
Correct Answer: Presence of foreign cell fragments like starch granules or fibers
Q19. Which regulatory document provides monographs and standards for herbal drugs in India?
- United States Pharmacopeia alone
- Indian Pharmacopoeia (IP)
- European Pharmacopoeia only
- Food Safety and Standards Act with no pharmacopoeial monographs
Correct Answer: Indian Pharmacopoeia (IP)
Q20. Which technique is most appropriate for quantifying volatile oil content in a herb?
- Hydrodistillation followed by GC analysis
- Colorimetric Dragendorff’s test
- Microscopic starch staining
- Loss on ignition at 900°C
Correct Answer: Hydrodistillation followed by GC analysis
Q21. What is the main purpose of collecting a voucher specimen during herb sourcing?
- To provide a sample for HPLC quantification only
- To act as a permanent taxonomic record and confirmation of identity
- To serve as the final packaged product for sale
- To determine microbial limits in the field
Correct Answer: To act as a permanent taxonomic record and confirmation of identity
Q22. Which of these is a pharmacopeial limit that helps detect excessive inorganic contaminants in herbs?
- Maximum permitted moisture content
- Total ash and acid-insoluble ash limits
- Minimum visible color intensity
- DNA sequence similarity threshold
Correct Answer: Total ash and acid-insoluble ash limits
Q23. Which anatomical feature distinguishes dicot root from monocot root in cross section used for identification?
- Presence of pith at center in dicot root
- Radial arrangement of vascular bundles in dicot root
- Vascular bundles in a ring typical of stems
- Scattered vascular bundles typical of monocot stems
Correct Answer: Radial arrangement of vascular bundles in dicot root
Q24. Thin layer chromatography (TLC) fingerprinting helps in authentication by:
- Providing microscopic anatomical charts
- Comparing characteristic spot patterns and Rf values with standards
- Measuring DNA content quantitatively
- Determining moisture content precisely
Correct Answer: Comparing characteristic spot patterns and Rf values with standards
Q25. Which heavy metal is commonly tested during herbal quality control due to toxicity concerns?
- Iron at any level
- Mercury, lead and arsenic
- Potassium as toxic heavy metal
- Calcium as contaminant
Correct Answer: Mercury, lead and arsenic
Q26. Which feature is characteristic of root drugs like Glycyrrhiza (licorice) when examined microscopically?
- Abundant secretory cavities in leaves only
- Vascular cambium with secondary xylem and phloem in root
- Presence of stomata on root epidermis
- Glandular hairs on root surface
Correct Answer: Vascular cambium with secondary xylem and phloem in root
Q27. A reliable pharmacognostic approach to detect powder adulteration with starch from wheat involves:
- Performing Dragendorff’s test
- Iodine test for starch and microscopic observation of starch granules
- Measuring total ash only
- Determining alcohol-soluble extractive value solely
Correct Answer: Iodine test for starch and microscopic observation of starch granules
Q28. In selection of herb sources, geo-authenticity refers to:
- Legal ownership documentation of farmers
- Specific geographical area linked to characteristic quality of the herb
- Any region where the plant grows wild
- Artificial cultivation in greenhouses only
Correct Answer: Specific geographical area linked to characteristic quality of the herb
Q29. Which marker compound type is most useful as a stability indicator during herbal formulation development?
- Volatile markers only
- Non-specific inorganic ash
- Specific active phytochemical marker known to degrade predictably
- Organoleptic aroma descriptors only
Correct Answer: Specific active phytochemical marker known to degrade predictably
Q30. According to WHO guidelines, authentication of herbal materials should ideally combine:
- Only organoleptic and color charts
- Macroscopic, microscopic, chemical and molecular methods
- Visual inspection and taste test exclusively
- Only DNA testing without other data
Correct Answer: Macroscopic, microscopic, chemical and molecular methods
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.
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