The primary role of the thyroid is to make and release two hormones into our bloodstream. The first hormone is trilodothyronine and the second is ithyroxine, (also called tetraiodothyronine). Given the obscure and difficult-to-pronounce names, you can see why these hormones are more commonly referred to by their abbreviated names of T3 and T4, respectively. Onced released, each of these hormones acts as a messenger. These messengers have the equally important job of communicating with various cells and tissues throughout your body.
The T3 and T4 hormones gather information from each cell in bloodstream, and they use that information to determine whether to increase or decrease the metabolic rate in the body. In addtion to regulating human body metabolism, these hormones also help in other ways. For instance, they help make more efficient use of your body’s intake of cholesterol and nutrients, thus ensuring proper brain development, and normal body growth.
There is a third hormone, calcitonin, produced by the thyroid gland. In addition to this third hormone, there are also four smaller glands, called parathyroid glands. These four smaller glands are attached to the larger thyroid gland. The job of calcitonin is to work cooperatively with the smaller parathyroid glands to keep an eye on the calcium and phosphorus levels in the bloodstream, maintaining them appropriately.
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