Which epithelium lines thyroid follicles?

Which epithelium lines thyroid follicles?

• A. Pseudostratified columnar epithelium
• B. Transitional epithelium
• C. Simple cuboidal epithelium
• D. Simple squamous epithelium

Answer: (C)

Thyroid follicles are lined by a single layer of cube-shaped cells called follicular cells. This simple cuboidal epithelium forms the wall around a lumen filled with colloid, the storage form of thyroid hormone precursors. The arrangement supports the synthesis and processing of thyroglobulin and its iodination to produce thyroid hormones. The other epithelial types appear in different organs—pseudostratified columnar in the respiratory tract, transitional in the urinary tract, and simple squamous in areas like alveoli and lining vessels—so they don’t line thyroid follicles.

Thyroid follicles are lined by a single layer of cube-shaped cells called follicular cells. This simple cuboidal epithelium forms the wall around a lumen filled with colloid, the storage form of thyroid hormone precursors. The arrangement supports the synthesis and processing of thyroglobulin and its iodination to produce thyroid hormones. The other epithelial types appear in different organs—pseudostratified columnar in the respiratory tract, transitional in the urinary tract, and simple squamous in areas like alveoli and lining vessels—so they don’t line thyroid follicles.