Morphology and histology of Cinnamon MCQs With Answer

Morphology and histology of Cinnamon MCQs With Answer

The morphology and histology of Cinnamon (genus Cinnamomum) cover macroscopic features—bark quills, leaf shape, and branching—and microscopic characters such as periderm structure, secondary phloem, stone cells, fibers, vessels, oil cells and calcium oxalate crystals. For B. Pharm students, mastering these diagnostic features is essential for correct identification, quality control and pharmacognostic evaluation of cinnamon drugs and powders. Important keywords include cinnamon bark, transverse section (T.S.), powder microscopy, secretory cells, lignified fibres, cinnamaldehyde and histochemical tests (phloroglucinol, Sudan III). This set emphasizes practical microscopy, staining reactions and distinguishing true cinnamon from cassia. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which botanical genus does commercial cinnamon belong to?

• Cinnamomum
• Curcuma
• Piper
• Mentha

Correct Answer: Cinnamomum

Q2. The primary commercial source of true cinnamon is which species?

• Cinnamomum cassia
• Cinnamomum verum
• Cinnamomum camphora
• Cinnamomum zeylanicum var. cassia

Correct Answer: Cinnamomum verum

Q3. Which volatile constituent is most characteristic of cinnamon bark aroma?

• Eugenol
• Cinnamaldehyde
• Limonene
• Menthol

Correct Answer: Cinnamaldehyde

Q4. Macroscopically, peeled cinnamon bark commonly forms what structure used commercially?

• Quills (rolled inner bark)
• Rhizomes
• Pods
• Leaves

Correct Answer: Quills (rolled inner bark)

Q5. Cinnamon leaves typically exhibit which type of venation?

• Pinnate venation
• Parallel venation
• Palma­te venation
• Reticulate without a midrib

Correct Answer: Pinnate venation

Q6. Which tissue forms the outer protective layer of cinnamon bark and contains suberized cells?

• Phellogen (periderm/cork)
Epidermis
• Endodermis
• Collenchyma

Correct Answer: Phellogen (periderm/cork)

Q7. In transverse section of cinnamon bark, which zone corresponds to the commercially used quill?

• Secondary xylem
• Secondary phloem (inner bark)
• Cork
• Primary cortex

Correct Answer: Secondary phloem (inner bark)

Q8. Which microscopic element in cinnamon powder indicates mechanical strength and is a sclerenchymatous cell?

• Parenchyma cells
• Stone cells (sclereids)
• Trichomes
• Guard cells

Correct Answer: Stone cells (sclereids)

Q9. Which histochemical reagent is commonly used to detect lignified cell walls in cinnamon sections?

• Sudan III
• Phloroglucinol-HCl (Wiesner test)
• Ferric chloride
• Molisch reagent

Correct Answer: Phloroglucinol-HCl (Wiesner test)

Q10. Essential oil in cinnamon is primarily stored in which microscopic structures?

• Vacuolated parenchyma only
• Oil cells and secretory cavities/glands
• Endodermal Casparian strips
• Tracheary elements

Correct Answer: Oil cells and secretory cavities/glands

Q11. Which type of cell wall thickening is typical of xylem elements observed in cinnamon wood and bark vessels?

• Primary thin walls only
• Secondary lignified walls with annular, helical or scalariform thickenings
• Suberized walls like cork
• Non-lignified cellulose-only walls

Correct Answer: Secondary lignified walls with annular, helical or scalariform thickenings

Q12. Presence of which crystals is a diagnostic microscopic feature in cinnamon tissues?

• Silica bodies only
• Calcium oxalate crystals
• Calcium carbonate spheres
• Uric acid granules

Correct Answer: Calcium oxalate crystals

Q13. Which cell type in cinnamon bark is primarily responsible for radial transport and storage and appears as rays in T.S.?

• Axial parenchyma
• Medullary rays (ray parenchyma)
• Sclereids
• Endodermal cells

Correct Answer: Medullary rays (ray parenchyma)

Q14. Which staining reagent is useful for detecting lipids/oils in cinnamon sections or powders?

• Phloroglucinol-HCl
• Sudan III or Sudan IV
• Ferric chloride
• Potassium permanganate

Correct Answer: Sudan III or Sudan IV

Q15. Which microscopic feature helps to distinguish true cinnamon (C. verum) from cassia in powder microscopy?

• Higher starch grains in true cinnamon
• Abundance of stone cells and thick cork in cassia compared to thinner, more delicate quills in true cinnamon
• Presence of trichomes only in cassia
• Blue fluorescence under UV only for true cinnamon

Correct Answer: Abundance of stone cells and thick cork in cassia compared to thinner, more delicate quills in true cinnamon

Q16. In cinnamon leaf histology, which layer contains photosynthetic chlorenchyma and may house oil cells?

• Palisade and spongy mesophyll
• Epidermal cuticle only
• Pericycle
• Periderm

Correct Answer: Palisade and spongy mesophyll

Q17. Which microscopic diagnostic characters are commonly described in cinnamon powder reports?

• Only epidermal scales and stomata
• Fragments of periderm, cork cells, stone cells, fibers, vessels, oil cells and calcium oxalate crystals
• Only starch grains and pollen
• Only tracheids without vessels

Correct Answer: Fragments of periderm, cork cells, stone cells, fibers, vessels, oil cells and calcium oxalate crystals

Q18. What is the primary function of sclerenchymatous fibers in cinnamon bark?

• Photosynthesis
• Mechanical support and tensile strength
• Secretion of essential oils
• Water absorption

Correct Answer: Mechanical support and tensile strength

Q19. Which pharmacognostic technique is most important for confirming identity of cinnamon raw drug and powder?

• Gas chromatography only
• Microscopy (T.S. and powder microscopy) combined with organoleptic and chemical tests
• Only taste test
• Soil analysis of cultivation site

Correct Answer: Microscopy (T.S. and powder microscopy) combined with organoleptic and chemical tests

Q20. Which feature under polarized light aids in identifying calcium oxalate crystals in cinnamon?

• They become invisible under polarized light
• They show strong birefringence (bright under polarized light)
• They dissolve under polarized light
• They fluoresce green under polarized light

Correct Answer: They show strong birefringence (bright under polarized light)

Q21. Which anatomical section is most useful for studying the arrangement of periderm, cortex and phloem in cinnamon?

• Longitudinal section of leaf
• Transverse section (T.S.) of bark or quill
• Radial section of seed
• Surface epidermal peel of root

Correct Answer: Transverse section (T.S.) of bark or quill

Q22. Which chemical test gives a yellow to brown coloration with cinnamon due to presence of aldehydes and phenolics?

• Molisch test
• Ferric chloride test
• Wagner’s reagent
• Ninhydrin test

Correct Answer: Ferric chloride test

Q23. Which structural feature in cinnamon bark often contains resinous or gummy substances conferring stickiness when powdered?

• Primary epidermis
• Resin ducts or secretory cavities lined with secretory epithelium
• Casparian strips
• Root hairs

Correct Answer: Resin ducts or secretory cavities lined with secretory epithelium

Q24. Which cellular element is indicative of storage of carbohydrates in cinnamon tissues?

• Vessel elements
• Parenchyma cells containing starch grains
• Sclerenchyma fibers
• Cork cells

Correct Answer: Parenchyma cells containing starch grains

Q25. Which of the following is a common microscopic vessel feature seen in cinnamon bark sections?

• Presence of vessel elements with bordered pits and occasional scalariform perforations
• Absence of any xylem elements
• Only sieve tubes with no vessels
• Chloroplast-rich vessels

Correct Answer: Presence of vessel elements with bordered pits and occasional scalariform perforations

Q26. Which part of the cinnamon twig shows secondary growth leading to formation of bark layers studied in histology?

• Primary apical meristem only
• Vascular cambium producing secondary xylem and secondary phloem
• Root meristem
• Leaf primordia

Correct Answer: Vascular cambium producing secondary xylem and secondary phloem

Q27. Which of the following microscopic observations in cinnamon powder is most characteristic of cassia (C. cassia) compared to C. verum?

• Finer, thinner quills with more oil cells
• Coarser, harder fragments with abundant thick-walled stone cells and cork
• Absence of calcium oxalate crystals in cassia
• Presence of glandular trichomes unique to cassia

Correct Answer: Coarser, harder fragments with abundant thick-walled stone cells and cork

Q28. Which microscopic technique helps visualize lipid droplets in oil cells of cinnamon most effectively?

• Phloroglucinol staining
• Sudan staining or fluorescent dyes like Nile red
• Gram staining
• Alcian blue for mucilage

Correct Answer: Sudan staining or fluorescent dyes like Nile red

Q29. What is the role of medullary rays in cinnamon stem histology relevant to pharmacognosy?

• They conduct water longitudinally only
• They facilitate radial transport and storage of metabolites, aiding identification in sections
• They produce essential oils directly
• They are absent in cinnamon stems

Correct Answer: They facilitate radial transport and storage of metabolites, aiding identification in sections

Q30. For routine quality control of cinnamon raw drug in a B.Pharm pharmacognosy lab, which combination of tests is most appropriate?

• Only organoleptic evaluation
• Microscopy (T.S. and powder), histochemical staining, and chemical tests for cinnamaldehyde
• Soil nutrient testing and leaf chlorophyll assay
• Only GC-MS without microscopy

Correct Answer: Microscopy (T.S. and powder), histochemical staining, and chemical tests for cinnamaldehyde

G S Sachin

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