thyroid gland: Quick Facts

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Detailed anatomical illustration of the human thyroid gland and surrounding structures, showing the right and left lobes, isthmus, nearby arteries, veins, nerves, lymph nodes, and cartilage in the neck.

Structural drawing of T3, reverse T3, and T4, showing the synthesis of T3 and reverse T3 from T4.

parafollicular cell; thyroid gland

Major glands of the human endocrine system. The hypothalamus stimulates the pituitary gland and influences food intake, weight regulation, fluid intake and balance, thirst, body heat, and the sleep cycle. Pituitary hormones stimulate growth, egg and sperm development, milk secretion, and release of hormones by other glands. The pineal gland may play a significant role in sexual maturation and the circadian rhythm. Thyroid hormones regulate the metabolic rate of tissues, stimulate the contraction of heart muscle, and are necessary for normal growth and brain development before birth and during infancy. Parathyroid hormone regulates calcium, phosphorus, and magnesium levels. The adrenal glands regulate salt and water retention, some reactions of the immune system, and blood pressure. The islets of Langerhans regulate blood sugar levels. The ovaries and testes produce hormones that regulate the reproductive system and that produce male and female secondary sex characteristics.

The principal glands of the female and male human endocrine systems.

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Topics

parafollicular cell thyroid hormone Goitrogen thyroid colloid triiodothyronine thyroidectomy hyperthyroidism hypothyroidism thyroid function test thyroid tumour ovary adrenal gland pancreas pituitary gland hypothalamus testis pineal gland thymus parathyroid gland kidney

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Key People

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Moritz Schiff

German physiologist

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George Redmayne Murray

British physician

Kocher, c. 1900

Emil Theodor Kocher

Swiss surgeon

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Anton, baron von Eiselsberg

Austrian surgeon

Sir Victor Horsley, c. 1910

Sir Victor Horsley

British surgeon

Male muscle, man flexing arm, bicep curl.

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Muscles of facial expression, human anatomy, (Netter replacement project - SSC). Human face, human head.

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