How do plants regulate their response to a specific chemical or physical signal using signaling molecules and signal transduction?

The activities of plants are coordinated by chemical compounds called hormones which are released by stimulated cells. These hormones exist in the form of molecules called signalling molecules. They are responsible for transmitting information to various receptor cells in different parts of the plant.

There are various types of signalling molecules. They vary in size, function and shape depending on the role they are expected to play. When a signalling molecule encounters a receptor cell, it binds to the cell membrane of the receptor cell, releasing a chemical signal which is picked up by the receptor cell.

The receptor cell converts the signal received to a form which it can easily comprehend and respond to by a process called signal transduction. The signal transduction process may be a simple one-step process or a series of steps which modify the signal by a relay of signaling molecules until it finally triggers a specific response in the cell. The response elicited in the cell ensures that the activity taking place in the cell is the correct one and that it is occurring in the right cell at the right time.