Parathyroid glands

The parathyroid glands are small endocrine glands that are located on the posterior aspect of the thyroid gland. They usually lie on the posterolateral surface of each thyroid lobe. Each person typically has four parathyroid glands, but the number can vary from two to six. The parathyroid gland is about the size of a pea and is a bit flattened and oval or round in shape. 

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