These pathways typically start with an internal stimulus — often coming from the hypothalamus or pituitary gland — and end in the target glands that release hormones into the blood, to get the real work of living done.

这些途径通常始于内部刺激——通常来自下丘脑或垂体——并以向血液中释放激素的靶腺结束，以完成真正的生活工作。