EM of a thyroid follicular cell. The cell has a spherical euchromatic nucleus and many tightly packed organelles. Its basal aspect is close to a fenestrated capillary. Short stubby microvilli (arrows) project from its apical surface into a colloid-filled follicular lumen. Intercellular junctions (circles) link lateral borders of the cells, whose basal surfaces rest on an inconspicuous basal lamina (arrowheads). 15,000×.