This section shows the follicular structure of the thyroid gland. The
walls of the follicles are composed of a single layer of cuboidal-
or columnar- shaped thyroid follicle cells with circular nuclei.
The follicles are filled with eosinophylic thyroid
colloid, the storage-form of thyroid hormone. The flattened nuclei
outside of the follicles belong, primarily, to capillary
endothelial cells.
