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Thyroid Cancer

  • Posted: 05/07/2012

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The Thyroid

The thyroid is a gland at the front of your neck beneath your voice box (larynx). A healthy thyroid is a little larger than a quarter. It usually can’t be felt through the skin.

The thyroid has two parts (lobes). A thin piece of tissue (the isthmus) connects the two lobes.

The thyroid makes hormones:

  • Thyroid hormone: The thyroid follicular cells make thyroid hormone. This hormone affects heart rate, blood pressure, body temperature, and weight. For example, too much thyroid hormone makes your heart race, and too little makes you feel very tired.
  • Calcitonin: The C cells in the thyroid make calcitonin. This hormone plays a small role in keeping a healthy level of calcium in the body.

Four or more tiny parathyroid glands are on the back of the thyroid. These glands make parathyroid hormone. This hormone plays a big role in helping the body maintain a healthy level of calcium.

The pictures show the front and back of the thyroid.
The pictures show the front and back of the thyroid.

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