endocrine gland, a ductless gland that produces and secretes hormones into the blood or lymph nodes, affecting metabolism and other body processes. The endocrine glands include the pituitary, pineal, hypothalamus, thymus, thyroid, parathyroid, adrenal cortex, medulla, pancreatic islands of Langerhans, and gonads. Cells in other structures, such as the GI mucosa, the kidneys, the heart, and the placenta, also have endocrine functions. Compare exocrine gland.
