Understanding functions and locations of epithelial tissues is essential for B. Pharm students because epithelia control absorption, secretion, protection, selective permeability and barrier formation across organs. This concise review highlights epithelial types — simple squamous, cuboidal, columnar, pseudostratified, stratified and transitional — plus surface specializations like microvilli, cilia and tight junctions. Learn anatomical sites (alveoli, endothelium, kidney tubules, intestinal mucosa, respiratory tract, skin, urinary bladder), glandular classification (endocrine vs exocrine; merocrine, apocrine, holocrine), basement membrane components and drug absorption relevance. Clinical correlations include metaplasia, carcinoma origins and epithelial repair. Solid grasp of these keywords — functions, locations, polarity, junctions and regeneration — prepares you for pharmacology and therapeutics. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which of the following best summarizes the primary functions of epithelial tissues?
- Structural support, fat storage, hematopoiesis, insulation
- Absorption, secretion, protection, selective permeability
- Contraction, impulse conduction, blood filtration, mineral storage
- Immune surveillance, neurotransmission, pigment production, elasticity
Correct Answer: Absorption, secretion, protection, selective permeability
Q2. Which epithelial type is best adapted for rapid exchange of gases and lining blood vessels?
- Simple cuboidal epithelium
- Simple columnar epithelium
- Simple squamous epithelium
- Stratified squamous epithelium
Correct Answer: Simple squamous epithelium
Q3. The small intestinal mucosa specialized for absorption is primarily lined by which epithelium?
- Stratified squamous epithelium
- Simple columnar epithelium with microvilli (brush border)
- Pseudostratified ciliated columnar epithelium
- Transitional epithelium
Correct Answer: Simple columnar epithelium with microvilli (brush border)
Q4. Which intercellular junction forms a permeability barrier near the apical surface of epithelial cells?
- Gap junction
- Tight junction (zonula occludens)
- Desmosome (macula adherens)
- Hemidesmosome
Correct Answer: Tight junction (zonula occludens)
Q5. Where would you expect to find pseudostratified ciliated columnar epithelium with goblet cells?
- Alveolar sacs of the lung
- Small intestine villi
- Trachea and upper respiratory tract
- Urinary bladder lumen
Correct Answer: Trachea and upper respiratory tract
Q6. Which cell surface specialization increases apical surface area for absorption in the proximal renal tubule?
- Cilia with dynein arms
- Microvilli forming a brush border
- Keratinized plaques
- Basal infoldings with mitochondria
Correct Answer: Microvilli forming a brush border
Q7. Which epithelial type lines the urinary bladder and is adapted for stretching?
- Stratified squamous keratinized epithelium
- Transitional epithelium (urothelium)
- Simple cuboidal epithelium
- Pseudostratified columnar epithelium
Correct Answer: Transitional epithelium (urothelium)
Q8. Which basement membrane components are key for epithelial attachment and filtration?
- Elastin and fibronectin
- Type IV collagen and laminin
- Type I collagen and proteoglycans
- Keratin and actin
Correct Answer: Type IV collagen and laminin
Q9. An endocrine gland differs from an exocrine gland because it:
- Releases products onto an epithelial surface via ducts
- Secretes hormones directly into the bloodstream
- Always secretes mucous only
- Is derived from mesenchyme rather than epithelium
Correct Answer: Secretes hormones directly into the bloodstream
Q10. Which mode of secretion involves release of cell fragments and secretory product together?
- Merocrine secretion
- Apocrine secretion
- Holocrine secretion
- Endocrine secretion
Correct Answer: Holocrine secretion
Q11. In epithelial polarity, which domain faces the lumen and often has microvilli or cilia?
- Basolateral domain
- Basal domain
- Apical domain
- Adhesion domain
Correct Answer: Apical domain
Q12. Which junctional complex provides strong mechanical coupling between epithelial cells and resists shear stress?
- Tight junctions
- Desmosomes
- Gap junctions
- Focal adhesions
Correct Answer: Desmosomes
Q13. Which epithelial feature is most directly relevant to oral drug absorption and bioavailability?
- Presence of cilia in airway epithelium
- Thickness and permeability of intestinal epithelium with microvilli
- Keratinization of skin epidermis
- Transitional epithelium in bladder
Correct Answer: Thickness and permeability of intestinal epithelium with microvilli
Q14. Goblet cells are specialized epithelial cells that secrete:
- Serous enzymes
- Mucus (mucin)
- Hormones into capillaries
- Keratin filaments
Correct Answer: Mucus (mucin)
Q15. Which epithelial-derived tumor is most likely to arise from glandular epithelium?
- Sarcoma
- Adenocarcinoma
- Glioma
- Leiomyoma
Correct Answer: Adenocarcinoma
Q16. Which protein family composes the channels of gap junctions for cell-to-cell communication?
- Integrins
- Connexins
- Claudins
- Cadherins
Correct Answer: Connexins
Q17. The airway epithelium moves trapped particles out of the respiratory tract primarily by:
- Peristaltic waves generated by smooth muscle
- Ciliary beating of pseudostratified columnar epithelium
- Absorptive transport across simple squamous epithelium
- Desquamation of transitional epithelium
Correct Answer: Ciliary beating of pseudostratified columnar epithelium
Q18. Which epithelium forms the outermost layer of the skin and provides mechanical protection?
- Simple cuboidal epithelium
- Stratified squamous keratinized epithelium
- Simple columnar epithelium
- Pseudostratified columnar epithelium
Correct Answer: Stratified squamous keratinized epithelium
Q19. Which feature distinguishes apocrine secretion from merocrine secretion?
- Apocrine releases vesicles via exocytosis without cytoplasm loss
- Apocrine involves shedding of apical cytoplasm with secretory product
- Merocrine destroys entire cell to release product
- Merocrine always secretes hormones into blood
Correct Answer: Apocrine involves shedding of apical cytoplasm with secretory product
Q20. Which epithelium would you expect to line the thyroid follicle and participate in hormone synthesis?
- Stratified squamous epithelium
- Simple cuboidal epithelium
- Pseudostratified columnar epithelium
- Transitional epithelium
Correct Answer: Simple cuboidal epithelium
Q21. Epithelial metaplasia often increases cancer risk because:
- Metaplasia always causes immediate necrosis
- Replacement cell type may be less suited to environment and prone to dysplasia
- Metaplasia increases tight junction strength preventing repair
- Metaplasia converts epithelium to muscle tissue
Correct Answer: Replacement cell type may be less suited to environment and prone to dysplasia
Q22. Which cell junction anchors epithelial cells to the underlying basement membrane?
- Adherens junction between lateral membranes
- Hemidesmosome
- Gap junction connecting cytoplasms
- Tight junction sealing the apical border
Correct Answer: Hemidesmosome
Q23. In renal physiology, which epithelial characteristic facilitates high rates of solute and water reabsorption?
- Keratinized stratified layers
- Apical microvilli and abundant mitochondria in proximal tubule cells
- Multilayered pseudostratified structure
- Thick basement membrane impermeable to ions
Correct Answer: Apical microvilli and abundant mitochondria in proximal tubule cells
Q24. Which claudin/occludin-containing structure directly affects paracellular drug diffusion?
- Desmosome
- Tight junction
- Gap junction
- Basal lamina
Correct Answer: Tight junction
Q25. A carcinoma arising from bronchial epithelium most likely originates from which epithelial type?
- Simple squamous epithelium
- Pseudostratified ciliated columnar epithelium
- Transitional epithelium
- Stratified non-keratinized squamous epithelium
Correct Answer: Pseudostratified ciliated columnar epithelium
Q26. Which epithelial adaptation increases basal membrane surface area to support active transport?
- Basal infoldings with mitochondria
- Apical cilia beating
- Keratinization of apical cells
- Loss of basement membrane
Correct Answer: Basal infoldings with mitochondria
Q27. Which statement about glandular exocrine classification is correct?
- The pancreas is purely endocrine with no exocrine component
- Exocrine glands secrete via ducts onto epithelial surfaces
- Endocrine glands always have ducts
- Holocrine secretion releases products by exocytosis only
Correct Answer: Exocrine glands secrete via ducts onto epithelial surfaces
Q28. Which epithelial change characterizes Barrett’s esophagus and increases adenocarcinoma risk?
- Normal stratified squamous epithelium replaced by columnar epithelium with goblet cells
- Simple squamous epithelium replaced by keratinized stratified squamous epithelium
- Respiratory pseudostratified epithelium replaces gastric mucosa
- Transitional epithelium appears in the esophagus
Correct Answer: Normal stratified squamous epithelium replaced by columnar epithelium with goblet cells
Q29. Which epithelial property contributes to rapid wound healing and regeneration?
- Low mitotic activity and limited stem cell pools
- High mitotic activity and presence of stem/progenitor cells
- Permanent differentiation with no basement membrane
- Lack of cell–cell junctions
Correct Answer: High mitotic activity and presence of stem/progenitor cells
Q30. In drug targeting, which epithelial location is most important for systemic oral drug uptake?
- Gastric stratified squamous mucosa
- Small intestinal simple columnar epithelium with extensive microvilli
- Skin keratinized stratified squamous epithelium
- Transitional epithelium of urinary bladder
Correct Answer: Small intestinal simple columnar epithelium with extensive microvilli
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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