Thyroid follicles. Light micrograph of a section through a thyroid gland showing the follicles. The follicles are lined by a single layer of cuboidal

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Thyroid follicles. Light micrograph of a section through a thyroid gland showing the follicles. The follicles are lined by a single layer of cuboidal epithelial cells (purple), which synthesise and secrete the iodine-containing hormones T3 (tri-iodothyronine) and T4 (thyroxine). The thyroid follicle is filled with a glycoprotein substance called thyroglobulin or thyroid colloid (red), which is a storage form of the thyroid hormones. When actively secreting hormones the lining cells are large and cuboidal, when less active the follicles are distended and the secretory cells flattened.

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Size: 5092px × 3432px
Photo credit: © OVERSEAS/COLLECTION CNRI/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: biological, biology, body, colloid, endocrinology, follicle, follicles, gland, healthy, histological, histology, hormonal, hormone, human, light, lm, micrograph, microscope, normal, secretion, section, sectioned, storage, t3, t4, thyroblobulin, thyroglobulin, thyroid, thyroxine, tissue, tri-iodothyronine