The endocrine system consists of glands that regulate vital functions through the release of hormones. The major endocrine glands are the pituitary, pineal, thyroid, parathyroids, adrenals, ovaries, and testes. The pituitary is called the "master gland" as it controls the functioning of the other glands. Glands such as the thyroid, adrenals, ovaries and testes regulate metabolism, stress response, reproduction, and sexual development through hormones like thyroid hormones, corticosteroids, estrogen, progesterone and testosterone.