What happens once a hormone reaches target organ or cell?

When a hormone reaches its target organ or cell, it binds to a specific receptor on the cell's surface or inside the cell. This binding triggers a cascade of events that leads to a change in cellular activity.

The first step is the binding of the hormone to its receptor. This binding causes a conformational change in the receptor, which activates it. The activated receptor then initiates a series of intracellular signaling pathways that ultimately lead to a change in cellular activity.

The specific effects of a hormone depend on the type of hormone and the target cell. For example, insulin, a hormone produced by the pancreas, causes liver cells to take up glucose from the blood. In contrast, glucagon, another hormone produced by the pancreas, causes liver cells to release glucose into the blood.

Hormones play an essential role in coordinating the activities of different organs and systems in the body. By regulating cellular activity, hormones maintain homeostasis and allow the body to respond to changing conditions.