Cell Signalling

This lesson covers:

  1. The process of cell signalling 

Cell signalling

Cell signalling is the process by which cells communicate with one another.


The steps in this process are outlined below: 

Illustration of cell signalling showing ligands binding to a cell receptor.
  1. A stimulus causes cells to secrete a specific chemical known as a ligand.
Diagram showing cell signalling with a ligand binding to a receptor on the cell surface.

2. The ligand travels to target cells where it binds to cell-surface receptors. These receptors have a specific shape that is complementary to the ligand.

Diagram illustrating the cell signalling process leading to a cellular response.

3. Binding of the ligand causes the receptor to change shape. This activates other molecules (usually enzymes) inside the cell to transmit the message and bring about a response.