Images Dated 21st April 1994
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Choose from 8 pictures in our Images Dated 21st April 1994 collection for your Wall Art or Photo Gift. Popular choices include Framed Photos, Canvas Prints, Posters and Jigsaw Puzzles. All professionally made for quick delivery.
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Featured 21 Apr 1994 Print
Illustration of follicles in the thyroid gland
Thyroid gland. Illustration of the microscopic cell structure of the human thyroid gland, with an outline of the whole gland superimposed. The white outline (at centre) represents the shape of the thyroid gland, located in the neck. Its cellular structure (background) consists of round follicles which produce thyroid hormone. Cut through, the follicles are composed of cuboidal epithelial cells (purple) which secrete hormones (light blue) into a central storage chamber. Each follicle is surrounded by a network of blood capillaries (red) which transport secreted thyroid hormone in the blood to the rest of the body. Nerves are yellow. Thyroid hormones control metabolism and growth
© JOHN BAVOSI/SCIENCE PHOTO LIBRARY