adrenal gland

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adrenal gland In vertebrates, an organ that secretes certain hormones. Many vertebrates possess multiple adrenal glands, but in mammals there is one gland close to each kidney. In tetrapods, each gland consists of a central medulla and an outer cortex. The medulla secretes adrenalin and noradrenalin, hormones needed when the animal is in an excited state and must engage in strenuous activity (e.g. fighting or fleeing). The cortex secretes sex hormones and other hormones concerned with regulating the water and salt balances of the body.

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