12唤 6 24 7 Epithelial cell has rich RER, G, secreting granules, microvilli, phagosomes, LYS, iodide pump, and receptors for thyrotropin(TsH): 1818 Epithelial cell has rich RER, G, secreting granules, microvilli, phagosomes, LYS, iodide pump, and receptors for thyrotropin (TSH)