Adrenal Gland

adrenal gland, also called suprarenal gland, either of two small triangular endocrine glands one of which is located above each kidney. In humans each adrenal gland weighs about 5 grams (0.18 ounce) and measures about 30 mm (1.2 inches) wide, 50 mm (2 inches) long, and 10 mm (0.4 inch) thick. Each gland consists of two parts: an inner medulla, which produces epinephrine and norepinephrine (adrenaline and noradrenaline), and an outer cortex, which produces steroid hormones. The two parts differ in embryological origin, structure, and function. The adrenal glands vary in size, shape, and nerve supply in other animal species. In some vertebrates the cells of the two parts are interspersed to varying degrees.