Thyroid follicles, light micrograph

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Light micrograph of a section through a thyroid gland showing the follicles. The follicles are lined by a single layer of cuboidal epithelial cells, 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 (not present), 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. Magnification: x200 when printed at 15cm wide.

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Size: 6016px × 4016px
Location:
Photo credit: © EYE OF SCIENCE/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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